This...isn't really a technical issue, Tethys.
Very few websites will take mail order, VERY few. Most take Paypal however so if you have access to the ability to make use of it (via family, for example) then that would be the logical way forward. You could easily buy a retail key digitally then download the game with ease then.
Your alternative is to, of course, buy it instore from a legit retailer.