Many items do not actually qualify for Canadians no digital items, some items do not even ship, etc... I know back when the white fat chocobo promo was up i was unable to purchase anything. A FC member was nice enough to give me a code they had.
When they say NA Promo really they should state United States Promo, lol
We are not viewed as part of NA for many promos (Not just Amazon or SE)

Perhaps you could find computer accesorries or something?
I am honestly waiting until the cloud mount comes to mogstation a while from now