I would like to share a story with you, it may help. I went through the PayPal / ebay process for a refund and won the process. I purchased a King Silver Sonic Cornet, that cost over $1000.00, this took place about seven years ago. I think the process is still about the same. You have to show proof for your claim.
I faxed in to PayPal, 3 letters on company letter head. (1) From a H.S. Band Director. (2) Music Store Manager. (3) Professional Musician / Instructor. I ask the seller if the horn had the original lacquered finish and he said yes.
The horn was re-lacquered and it changed the tone quality of the horn. Had photos to show the issues.
If you can get some type of proof from experts like a local hobby shop or member of a model railroad club, & photos, this can bring you a win