For anyone interested in how this turned out, I sent the gentleman in question a "Letter before action" and he sent me my money within 5 days as cash in an envelope which also covered my demand for the cost of sending the letter (by registered signed for 1st class post) so all his shenanigans cost him the original eBay price and an additional £3.60.

Online sources say a Letter before Action resolves 86% of all disputes before court action when someone's pulling a fast one.....believe it !

Thanks again for all the responses.