Yes, you can. I am not positive, but I believe amazon lets you use your American amazon account info too. As for conversion fees that would vary by who you have your credit card with. Also I'd use google chrome because they automatically translate into English.
Well I finally got my code from AMD, but uplay says 'a ubisoft service is not available at the moment' and has been for the last 12 hrs... so yeah this whole thing is pretty shitty.