I think there's an entire thread dedicated to identifying counterfeit Mac items on Specktra. Personally, I check the Ebay seller's rating and reviews before I purchase. You also find limited edition items at outlet stores here in US but I think the LE items pop up (if at all they do) much later after the collection's original launch date. So there's some waiting involved and very low guarantee that you'll get what you are looking for. Amazon sells LE Mac items too, I've never purchased it this way but you do find reviews on the seller.