1) ensure the revolver is unloaded and safe. 2) open the cylinder - Rossi marked their revolver model number on the frame behind the cylinder crane, ie: M31 etc.
No published sn data. You will have to call Rossi
50-200
Rossi M88: That may depend on when it was made. What is the serial number? That may help.
Rossi model number 31 had a 4" barrel and was discontinued in 1985. Model 68 came with a 2 or a 3" barrel. There is no model 38 Rossi. Model 88 and 88/2 only came in stainless steel finish. They also had a 2 or 3" barrel. Rossi did make the "Rossi Double Action Revolver" which has no model number. It was 5 round in the 38 special caliber, came with 3 or 6" barrel, adjustable rear sight, fixed ramp style front sight, blued or nickel finish, wood or plastic grips, and was produced from 1965 to 1991. Since you are not able to find the model number, it is very likely this is the gun you have.
No published sn data that I am aware of.
You will have to call Rossi to find out.
The Rossi model 31 had a 4in.barrel only,while the model 68 could be had in a 2in,or 3in barrel(nickel finish only on the 3in.barrel).I hope that you find this informative.
50-200
$100-$225, depending on condition.
Rossi
100-300
100-300 or so