That is not much to go on.
Any chance that you have access to the original box which would have a product code on the label?
The gold fill was done after it left the factory.
The wood grips are probably not original either. . . . . I also changed mine to wood grips
Is what you have a Mountain Gun?
A Mountain gun is 4" tapered barrel, Round Butt frame, Black ramp and black notch rear sight, black powder bevel on front of cylinder. It would have shipped with rubber grips