First a suggestion. DO NOT send any payment ever until you are 100% confident in the knowledge of all of the details of a transaction. I have learned this the hard way. If you leave details open, hoping for the best in the seller, every now and then you will be frustrated when you don't get it. If I am hazy about anything, I make sure I discuss it with the seller before payment goes out.

In this circumstance, you have outs. First step, contact the seller with a thorough explanation of what is wrong, and what you want done about it. Make it clear that you are dissatisfied with the transaction and intend to pursue it with eBay and Paypal. Give him a reasonable time to respond (for me that is 3-5 days).

If the seller contacts you, try to negotiate a remedy. If not, pursue your grievance vigorously with eBay and Paypal. Do not do a thing with the feedback until the issue is resolved. When it is, leave your honest impression of the transaction.

Hope this helps. In my experience, every 50 or so eBay transactions, a problem pops up. I view it as part of the price you pay for using ebay, and I am OK with that. I have never, not once, had a problem with any aspect of any transaction I have ever had with a club member.