I've never dealt with that kind of thing before. I do come across sellers that say they only ship to the US but when I ask if they ship to Ireland they say yeah and I just pay through paypal.
I have to say I've been pretty lucky buying online. And selling. Haven't had a problem.
I even got payed by mail from Denmark I think. Buyer just sent it in inside a book in a package. And it was all perfect.
I guess it's a thing of trust.