Butt or inside the crane area
You will need to call S&W
If it has one, it will be located inside the crane area.
The Model 16 was not made in 38 Special.
Yes
No serial number provided
J frame, usually in 38 special
The gun is likely a Harrington & Richardson (H&R) model 925. The caliber is .38 Smith and Wesson (S&W) special, not to be confused with .38 special (SPL). You must shoot the .38 S&W ammo, not .38 spl.
IT IS A 1957 MODEL OF THE COLT DETECTIVES SPEC .38
25-65 USD or so
198x.
50-400 usd
Impossible to answer without knowing who the maker is.