That's a good gun you have there. From your photos the grips look real nice and your gun appears to have close to around 85% nickel finish from what I can tell. That finish compared to blue doesn't look as pleasant to the eye, but that's the way nickel is and what's remaining is considerable. If everything's original and has a decent bore, if it functions well then value should be around $400. That gun will increase in value if left alone. If you want it to look new then buy something new. Try finding a nice vintage holster for it, cause if you go to sell it that will increase the value along with a letterfrom Roy Jinks at S&W.