any ideas on value of the following,
BSA RS1 reflex sight, must have bought it 40 odd years ago,copied the details from an old advert in airgun world.

Webley Senior my dad bought it in the 50s came to me about 1979, showing some wear so I stripped it and sent it to Webley for re-bluing Feb 1980
came back pristine, still have receipt it cost £9.55 posted back, fitted new spring breech seal and used it for years, left hand side blue wearing to brown where its laid down, so whats it worth, comes in a wooden box with a tin of pellets, receipt from Webley and print out "stripping the Senior by Eddie Barber" in Airgun World would cost a fortune to post because of the weight, cheers Tezz PS pics available