In researching an item I was interested in purchasing in the USA kept coming across Item does not ship to Canada. It appears it's being caused by a recent change on dot com. See attached started discussion and screenshot.
https://community.ebay.com/t5/Selling/International-shipping-defaulting-to-off/m-p/30709564
"Hi everyone! I recently realized most of my listings did not have the international shipping allowed (Global Shipping Program). I only use the "sell similar" when making new listings. It seems that whenever I do this on a listing that does have the Global Shipping Program enabled, the new listing still defaults to domestic only. Is there a way to fix this?"

Changing country only gives USA option. Hit this view 4 times out of 4 for US sellers.
-Lot