Magento 2.4.2: How to change tax label from Tax to Tax(PST/GST/HST)?

We got a custom shipping module created to handle shipping to addresses from within the US and Canada. I would need to change tax label from Tax to Tax(PST/GST/HST) in the payment page only when the destination country is Canada. Below is the whole script handling custom shipping. How can I achieve it?

<?php

namespace PerfectmakeupmirrorsCustomShippingModelCarrier;

use MagentoQuoteModelQuoteAddressRateRequest;
use MagentoShippingModelCarrierAbstractCarrier;
use MagentoShippingModelCarrierCarrierInterface;
use PerfectmakeupmirrorsPmmFedexModelPmmFedexCarrier;
use MagentoFrameworkAppResourceConnection;

/**
 * Custom shipping model
 */
class Customshipping extends AbstractCarrier implements CarrierInterface
{
    const FEDEX_METHODS = [
        'EUROPE_FIRST_INTERNATIONAL_PRIORITY' => 'Europe First Priority',
        'FEDEX_1_DAY_FREIGHT' => '1 Day Freight',
        'FEDEX_2_DAY_FREIGHT' => '2 Day Freight',
        'FEDEX_2_DAY' => '2 Day',
        'FEDEX_2_DAY_AM' => '2 Day AM',
        'FEDEX_3_DAY_FREIGHT' => '3 Day Freight',
        'FEDEX_EXPRESS_SAVER' => 'Express Saver',
        'FEDEX_GROUND' => 'Ground',
        'FIRST_OVERNIGHT' => 'First Overnight',
        'GROUND_HOME_DELIVERY' => 'Home Delivery',
        'INTERNATIONAL_ECONOMY' => 'International Economy',
        'INTERNATIONAL_ECONOMY_FREIGHT' => 'Intl Economy Freight',
        'INTERNATIONAL_FIRST' => 'International First',
        'INTERNATIONAL_GROUND' => 'International Ground',
        'INTERNATIONAL_PRIORITY' => 'International Priority',
        'INTERNATIONAL_PRIORITY_FREIGHT' => 'Intl Priority Freight',
        'PRIORITY_OVERNIGHT' => 'Priority Overnight',
        'SMART_POST' => 'Smart Post',
        'STANDARD_OVERNIGHT' => 'Standard Overnight',
        'FEDEX_FREIGHT' => 'Freight',
        'FEDEX_NATIONAL_FREIGHT' => 'National Freight'
    ];
    const SHIPPING_STANDARD = 'STD';
    const SHIPPING_2ND_DAY = '2DY';
    const SHIPPING_OVERNIGHT = 'ON';
    protected $_shipping_mode_strings = array(
        self::SHIPPING_STANDARD => 'Standard Ground',
        self::SHIPPING_2ND_DAY => 'Second Day',
        self::SHIPPING_OVERNIGHT => 'Next Day Air',
    );

    /**
     * @var string
     */
    protected $_code = 'customshipping';

    /**
     * @var bool
     */
    protected $_isFixed = true;

    /**
     * @var MagentoShippingModelRateResultFactory
     */
    private $rateResultFactory;

    /**
     * @var MagentoQuoteModelQuoteAddressRateResultMethodFactory
     */
    private $rateMethodFactory;

    /**
     * @var PerfectmakeupmirrorsCustomShippingHelperData
     */
    private $helper;

    /**
     * @var PsrLogLoggerInterface
     */
    protected $_logger;

    /**
     * @var PerfectmakeupmirrorsPmmFedexModelPmmFedexCarrier;
     */
    private $carrierFedex;

    /**
     * @var MagentoFrameworkAppResourceConnection;
     */
    protected $resource;

    /**
     * @var MagentoFrameworkAppResourceConnection;
     */
    protected $scopeConfig;

    /**
     * @param MagentoFrameworkAppConfigScopeConfigInterface $scopeConfig
     * @param MagentoQuoteModelQuoteAddressRateResultErrorFactory $rateErrorFactory
     * @param PsrLogLoggerInterface $logger
     * @param MagentoShippingModelRateResultFactory $rateResultFactory
     * @param MagentoQuoteModelQuoteAddressRateResultMethodFactory $rateMethodFactory
     * @param MagentoFrameworkAppResourceConnection $resource
     * @param array $data
     */
    public function __construct(
        MagentoFrameworkAppConfigScopeConfigInterface $scopeConfig,
        MagentoQuoteModelQuoteAddressRateResultErrorFactory $rateErrorFactory,
        PsrLogLoggerInterface $logger,
        MagentoShippingModelRateResultFactory $rateResultFactory,
        MagentoQuoteModelQuoteAddressRateResultMethodFactory $rateMethodFactory,
        PerfectmakeupmirrorsCustomShippingHelperData $helper,
        PerfectmakeupmirrorsPmmFedexModelPmmFedexCarrier $carrierFedex,
        MagentoFrameworkAppResourceConnection $resource,
        array $data = []
    ) {
        parent::__construct($scopeConfig, $rateErrorFactory, $logger, $data);

        $this->rateResultFactory = $rateResultFactory;
        $this->rateMethodFactory = $rateMethodFactory;
        $this->carrierFedex = $carrierFedex;
        $this->_logger = $logger;
        $this->helper = $helper;
        $this->resource = $resource;
        $this->scopeConfig = $scopeConfig;
    }

    /**
     * Custom Shipping Rates Collector
     *
     * @param RateRequest $request
     * @return MagentoShippingModelRateResult|bool
     */
    public function collectRates(RateRequest $request)
    {
        if (!$this->getConfigFlag('active')) {
            return false;
        }
        
        if ($request->getDestCountryId() == "CA") {
            // Shipping to Canada.
            // 1. Get the array of method objects from $fedex_results object
            // 2. Loop through the array of method objects to set carrier.
            // 3. Set carrier to custom shipping.
            // 4. Add brokerage to the shipping cost based on the table canada_brokerage_fees.
            $fedex_results = $this->carrierFedex->collectRates($request);

            // MagentoQuoteModelQuoteAddressRateResultMethod $methods
            $methods = $fedex_results->getAllRates();
            foreach ($methods as $method) {
                // 3. Set carrier to custom shipping.
                $method->setCarrier($this->_code);
                $method->setMethodTitle("(including brokerage and duty)");
                $method->setCarrierTitle("");

                // Get subtotal from the $request object.
                // The request object is not giving the subtotal directly.
                // Using Quote object.
                // Refer https://magento.stackexchange.com/questions/341393/magento-2-4-2-how-to-get-order-sub-total-in-my-custom-module/341410#341410
                $quote = null;
                $items = $request->getAllItems();
                foreach($items as $item) {
                    /** @var Quote $quote */
                    $quote = $item->getQuote();
                    break;
                }
                if (!$quote) {
                    return false;
                }
                $subtotal = $quote->getSubtotal();                

                // Convert subtotal from USD to CAD
                // Get current CAD rate.
                $current_usd_to_cad_rate = $this->get_magento_system_info("pmm/currency_conversion/usd_to_cad_conversion");
                $subtotal_cad = $subtotal * floatval($current_usd_to_cad_rate);

                // Use table canada_brokerage_fee in Magento DB
                // Create DB connection
                // http://blog.chapagain.com.np/magento-2-run-custom-sql-query/
                $connection = $this->resource->getConnection();
                $tableName = $this->resource->getTableName('canada_brokerage_fees');

                // Compute brokerage.
                // Fetch relevant fee from the table canada_brokerage_fees 
                // based on the merchandise total.
                $sql = $connection->select()->from($tableName)->where('max_merchandise_cost <= ?', $subtotal_cad)
                ->order('brokerage_cost_cad DESC')->limit(1);
                $result = $connection->fetchAll($sql);                
                $brokerage_cost_cad = $result[0]['brokerage_cost_cad'] ?? 0;

                // TODO
                // Compute duty and add it to brokerage_cost_cad.
                // All mirror and skin care products are duty free.

                // Set new price with brokerage added to the shipping cost.
                $method->setPrice($method->getPrice() + $brokerage_cost_cad);
            }
            return $fedex_results;
        } elseif (($request->getDestRegionCode() == "AK") || ($request->getDestRegionCode() == "HI") || ($request->getDestCountryId() == "PR")) {
            // For Alaska, Hawaii, and Puerto Rico
            // We want to get the shipping computation using Fedex

            $fedex_results = $this->carrierFedex->collectRates($request);
            // 1. Get the array of method objects from $fedex_results object
            // 2. Loop through the array of method objects to set carrier.
            // 3. Set carrier to custom shipping. 

            // MagentoQuoteModelQuoteAddressRateResultMethod $methods
            $methods = $fedex_results->getAllRates();
            foreach ($methods as $method) {
                $method->setCarrier($this->_code);
                $method->setMethodTitle("(including brokerage and duty)");
                $method->setCarrierTitle("");
            }
            return $fedex_results;
        }

        // Below Processing is for Mainland USA.
        // Custom Shipping needs to be computed.
        /** @var MagentoShippingModelRateResult $result */
        $result = $this->rateResultFactory->create();

        /** @var MagentoQuoteModelQuoteAddressRateResultMethod $method */
        $method = $this->rateMethodFactory->create();

        $method->setCarrier($this->_code);
        $method->setCarrierTitle($this->getConfigData('title'));

        $method->setMethod($this->_code);
        $method->setMethodTitle($this->getConfigData('name'));

        $this->_logger->info(__FILE__ . ': At Start');

        // Get all the items.
        // NOTE: This getAllItems here is related to Quote and not the order.
        if ((!($items = $request->getAllItems())) or (count($items) == 0)) {
            return FALSE;
        }

        //Standard code commented. Custom code added.
        //$shippingCost = (float)$this->getConfigData('shipping_cost');
        $shippingCost = (float)$this->helper->compute_standard_shipping_cost($items);

        $method->setPrice($shippingCost);
        $method->setCost($shippingCost);

        $result->append($method);

        return $result;
    }

    /**
     * Get all the allowed methods for Custom Shipping. This sends the CustomShipping
     * method as well as all the allowed methods of Fedex. This is required to ensure
     * the Fedex shipping methods to be considered as valid methods.
     * 
     * @return array
     */
    public function getAllowedMethods()
    {
        $custom_shipping_methods = [$this->_code => $this->getConfigData('name')];
        $allowed_methods = array_merge($custom_shipping_methods, $this->FEDEX_METHODS);
        return $allowed_methods;
    }

    /**
     * get_magento_system_info - receives the path as parameter.
     * This parameter holds the path to the field.
     * This function returns a value in Magento core_config_data table.
     * 
     * @param string $path
     * @return string $config_data
     */
    private function get_magento_system_info($path)
    {
        // Refer https://store.magenest.com/blog/get-set-config-data-programmatically-magento-2/
        // Refer https://firebearstudio.com/blog/how-to-write-and-get-config-values-by-scope-in-magento-2.html

        // Call functions to get config data with default (global) scope
        return $this->scopeConfig->getValue($path);
    }
}