10 year warranty was advertised.
That should have been a warning. No manufacturer would give a 10 year warranty on a timing belt. The replacement schedue is usually between five and seven years.
I take it you didn't read eBay's warnng to buyers that "they do not guarantee the existence, quality, safety or legality of items advertised, or the truth or accuracy of descriptions". You may have thought twice before buying a critical engine component from an unknown selle here.
I'm afraid it's too late to do anything through eBay or PayPal, their own buyer protection schemes only last for 30 days.
If you paid by credit or debit card your best hope is that your card issuer may be able to help. Credit cards carry additional rights under the consumer credit act, but whether these would cover consequential loss I don't know. I imagine that all a debit card would cover would be the cost of the timing belt.
Failing the above you might have some statutory consumer rights. However, this sounds like a cheap Chinese copy and if your seller is in China it's end of story. Even if they're a UK business seller I suspect it may be hard work to get any money back. I would advise consulting a solicitor or Citizens advice before doing anything.
Good luck, I'm afraid you're going to need it!
