Word of warning, do not post about ebay items you have won until you have them or you are sure they have been posted. If that is a genuine vinyl cape and someone is able to tell from the auction pictures and description that they are, a less scrupulous collector might contact your seller and make them a better offer. From the ebay auction description the seller gave (which took me about 2 mins to find on ebay given the info you supplied), they are making out like the cape is genuine, but they aren't really sure. Normally, that would point to fake, but only a close look when you have the item in hand will probably tell in this circumstance.
cheers Jason