LOL i probably would be flattered that a scammer would want my art prints, from Europe no less. Some countries have a way to confirm the address to the card. If you have paypal, they will do this for you. They will tell you on the order detail screen if the card holder has a confirmed delivery address. Paypal will however take the money out of the account if it is a fraud. Even a money order is iffy because of counterfeiting. Cash a money order and its 2 weeks at least before a bank knows. The best way of payment in my experience is a US USPS postal money. When cashing at the post office they have a way to make sure that it is legal tender. Or maybe Western Union money?
You really have nice prints (looked at your website) it would be a shame to be scammed out of prints.