a) 30 day and 180 day prepaid game time options were removed. You can only purchase 60 day prepaid gametime. Alternatively you can subscribe for a month and cancel the recurring subscription before the next renewal date.
This link should go to the 60 days prepaid game time purchase.
b) Address works fine here, if you scroll down you should see a list for regions and you can select EU (GB) from there. Your browser might also have set preferred web page language to en-us. See my older posts about the matter and tips on how to change it: