We accept all major credit cards as a method of payment and we do accept Canadian billing addresses. You may however need to remove any spaces or dashes from the zip code or postal code in order for our form to accept it.
For example, if your postal code is A1A 1A1 enter it into our form as A1A1A1.
If our system still doesn't allow you to submit your postal code, try submitting with 00000 and then updating once your account sign up is complete. We know this is a weird workaround and are hoping to resolve the issue sooner than later.
Update December 2020: We believe that we have resolved this issue and postal codes can now be entered with proper space. We are leaving this article live in the event that you run into an issue. Please contact support and we'll be happy to help.