If you bought the coin on eBay, and paid for the coin with PayPal, you can file a claim with PayPal, and they will make an effort to correct the issue. You stand a better chance of applying pressure that way. You might still not collect anything, but you will have tried. PayPal has a deductable of $25.00, so if the coin was low cost, that might keep you from collecting, but at least you won't let the seller get by without any intervention. It is a real shame that the 1% of (bad) sellers are not honorable, because it sure takes the fun out dealing on eBay and on-line. Luckily that 1% are the exception...not the rule. Good luck with it.