Sitting in traffic and just happened to glance into a skip out of boredom to see the end of the stock poking out of a pile of rubbish. Parked. Jogged back...
...and look what i found. Please correct me if I am wrong, but from checking through Garvin's vintage gallery this is a HAENEL Model 10 as denoted by the X stamped on the top of the barrel, and circa 1931'ish?
So whistling a merry tune I nipped down to the workshop at home, whipped out the wire wool and WD40, sanded back the stock. And an hour later the transformation (with a few drops of Tru Oil) is complete. And best of all, she works! Complete with the little barrel insert you remove and load before cocking, and happily spitting out .177 consistantly enough to put a very big smile on my face. So NOT just a wall-hanger.
Have no idea how to strip down further as a lot of rivets in place, but I don't believe anything else is required. The screws you can see on the side are for undoing the retainer pins relating to the 'wire rod' internals used to cock the action. Gubbins inside seems remarkably good order. Smooth not 'gronchy' when you cock, and complete enough not to warrant changing anything.
...pics to follow (just wrestling with Photobucket as can't remember which bit i copy)