When we list from Canada on dotCOM, we can only use Flat Rate Shipping.
However, at least in theory, we can set several different rates, depending on destination.
I have several instances where I have been unable to add overseas destinations after successfully setting up Canada as destination.
My answer was to find a listing that included both Canada and Overseas as separate rates and make that a Template.
I do have the luxury of selling items that do not vary much in dimensions and weight. YMMV.