Absolutely, you can file a well argumented and documented small claim law suit, and the odds are pretty much on your favor, the reason why you don't see that happening often, is because it is a somehow lengthy process, and requieres time and several steps, but all that time and effort can add up to the compensation owed to you. Another helpful step would be to specify that the whole case is non confidential, and if you end up winning the case, you could and should make it public, this would help thousands other potential victims of ebay's arbitrary policies, to go forward with their claims against ebay's sistemic siding with buyers in order to scam the sellers. EBay truly have a very faulty set of policies, and the best (or worst) thing of all is that an issue like scam, fraud, and extortion, can be replicated over and over with the same results, EBay always sides with the buyer and rips off the seller. Remember, you as a seller, are paying a very high commission fee for your sales to EBay, so they should provide a much more secure environment for honest sellers, specially sellers with a long history of satisfied buyers on EBay. All of this is can be added arguments on a court hiring, after all, it's not that difficult to explain when you have been robbed or scammed, how is it that it happened, and how EBay allowed and enabled buyers to defraud you in the first place. Don't be intimidated, EBay does have a huge army of lawyers working for them but, you can very easily convince a jury and judge, that all that legal bullet proofing on Ebay's side, is simply there to allow or help them get away with their unfair business practices.
