crosman 451 valuation

[hawkdriver]

I have owned a crosman 451 for many years, and decided its time for it to go along with lots of other shooting stuff, ill health and no shooting mojo has sort of woken me up to the amount of stuff i own but dont use, boxed but box is tatty, complete with crosman bulbs x5 with crimped on ends in box for these, instruction book, havnt ever shot it in the time i've owned it, no grunched screws, pretty much original but obviously been used sometime in its life, opinions / valuations would be welcomed, prior to selling, thanks