Smith and Wesson Model 1
22-72
S&w
All of them have a sn.
A .22 caliber Iver-Johnson Cadet revolver.
300-500
Impossible to answer without knowing who made it.
Best left to a gunsmith.
l Blue Book of Gun values
25-50 USD
No such S&W model number.
Sauer, Schmidt, Rohm
50-500 usd