Hi ..If one had good reason to believe an item on ebay is stolen property, the proper course of action would be to report it to the police, who would contact ebay..
Here is Buyer Protection for items not received or not as described..
http://pages.ebay.ca/help/buy/paypal-buyer-protection.html
Claims for refund must be filed within 45 days of payment and best is no later than day 43. Always try to work with seller first.