These are very nice air pistols. You will have to make the decision if you want it repaired. But one in EXCELLENT Condition is worth about $115. Less if it shows ware and is beat up. So it's really up to you.
I would do a search on the web for "Airgun Repair" and locate a shop near you to have it rebuilt.
Gun shop or sporting goods store
it is a Model 39-2 9mm pistol
Cartridge
value of smith & Wesson model 5906 pistol
Smith&Wesson model 14
A fine pistol.
Smith and Wesson 6909 Stainless steel semi-auto pistol stopped produvtion in 2001
No such model in the S&W line.
No
No such model number.
Smith and Wesson 9mm Model 39-2 Chrome finish.
Impossible to know the exact model from just the sn.