I buy things from eBay all the time. *loses count of numerious FF collectibles she's always buying* Unfortunately any Oddworld stuff I see on there, I either already have, or it's mostly just games and that. I've found it pretty reliable, just stick to sellers who have high feedback and you should be okay.
Anyways, I have that T-shirt already.
Thus why I did not bid.
And it is a promotional T-shirt, so you'll never find one of those in a shop.
Abe Babe...