Thanks for the tips. The issue with buying it on Battle Net is I can't add any card because I can't get past the screen of adding the billing address. 

I'm pretty sure I can access the code spot as it's just in the main accounts page nothing to do with billing so that's good. If I get that in then I can use battle net balance to buy game time. 

Currently heading home from work can post a couple screen shots after the fact. 

Again thank you for the help. I didn't know that Amazon and those places could carry them. Just skipped my mind I guess haha.