Need a sn to date it.
69-70
GunBroker.com
CHeck with the maker of the grip.
Take it to a gunsmith
250-500
Good condition with orig grips blue $1000 nickel $1400.
I can say that the Smith and Wesson model 15-3rd variation was produced between the years 1967-1976.I can also say that in 1968,they deleted the diamond grips on this model.I hope that this helps?
Wood
Depending on the exterior condition with pearls, $700.00 to $900.00.
On the bottom of the grip. It is sometimes covered up by the wood of the grips. Take them off.
crimson trace grips for smith and wesson 39
Try e-gunparts.com, gun shows, want ads.