What you are doing is called Dropshipping and is allowed on eBay provided that your supplier knows that you are reselling under your own name.
The cost your supplier charges you is not the business of your customer.
The location of the goods is the important part.
Location is JAPAN not Canada, since your customers may have import fees charged on their doorstep, even though Canada has a Free Trade Agreement through the Comprehensive and Progressive Agreement for Trans-Pacific Partnership along with some dozen other nations.
I am not sure about what the duty-free allowance and tax-free allowance is for imports from Japan. @zee-chan-jpn-books can you help on this?
You may want to add to your listings this boilerplate that eBay supplied some years ago to give notice that your customers may have to pay duty (or more likely sales taxes) on their purchase.
Import duties, taxes and charges are not included in the item price or shipping charges. These charges are the buyer's responsibility. Please check with your country's customs office to determine what these additional costs will be prior to bidding/buying.
