Thanks for your feedback - my thinking was that in any event of a buyer claiming non receipt I could claim back against the post office up to £20. Never in a million years did I expect a buyer to confirm receipt to me after already claiming to eBay it was lost to get a refund.

I've got the time and the money to pursue him through the courts without any concern for the outcome so I'll continue down that route. If they have to jump through a few hoops of my making then at least I'll feel like I'm getting my moneys worth :-), ..... might stop them doing it to someone else as well.