As per: https://schappi.com/tips/carrier-calculated-shipping-without-advanced-shopify-or-shopify-plus/ It states that:
"Hidden away in a Shopify Support Article is the little known fact that you can in fact get “Third-party carrier-calculated shipping rates” on a “Basic Shopify” or “Shopify” pricing plan without paying for Advanced Shopify or Shopify Plus."
"Third-party carrier-calculated shipping rates can be added to any plan for a monthly fee. All you need to do is contact Shopify Support."
How does one go about doing this as the "Contact Shopify Support" link sent me here
Any help is very much appreciated
You can use this link to contact the support via chat: Shopify support.
FYI, To get the carrier calculated shipping feature, there are three options;
You can then contact the support to enable this.