Hi Chaps,
Got it
many thanks to all. I also heard from Garvin (the original poster/owner) unfortunately this rifle was sold as parts, so the stock and all parts are now scattered. However at least I do have proof that Wilkinson did indeed mark their air weapons. Of course the big challenge now it to find one! So if anyone ever happens across 'any' Wilkinson marked air gun pleased drop me a line.
Very best to all, Roy.