Compare it to known examples.
Normally stamped on the left side of the frame for autos, and on the butt for revolvers.
It is a J frame.
Call S&W and they will tell you.
Contact S&W
Standard Catalog of Smith and Wesoon by Supica and Nahas
Standard Catalog of Smith and Wesson, 3rd ed.
Check the auction sites.
You must call S&W to find out.
No
You must call S&W to find out.
Recommend you find a good gunsmith.
You need to find a firearms instructor.