Seems like we could be talkin about the same copy Andy , I know when the Eric Mercury was found it was 1978/79 , Steve(kitty)wells , Rug and Wilkie had all sold there records to fund a trip to the States , with the help of John Manship who supplied them with some addresses to visit . It was Kitty who found the Eric Mercury in a thrift shop in Philadelphia.in a right dodgy area they were glad to get out of.
They were all mates of mine and lived in Northants , there was a good chance that it was Kitty who was at the Fleet and came on stage when you played it as we went there during that period , but what remains a mystery is i can clearly remember him telling me he had traded it with Chris plant for a Del Larks , Kitty had probably owned it a couple of years by then so theres a chance Dave raistrick had found another copy or was it Dave he did the trade with.