The price is gonna last for another two days. I don't know how limited their keys are, but I code my code in the email quickly.
I'm not quite sure how this region stuff works, but the following two lines are under the item page:
Worldwide Region Free - This product code can be activated in any country, without any restrictions.
CUSTOMERS FROM GERMANY, AUSTRIA, AUSTRALIA, NEW ZEALAND, ISRAEL, SAUDI ARABIA AND JAPAN WON'T BE ABLE TO ACTIVATE THE GAME WITH THEIR IP.