Three comments: I don't see many nickeled 32-20's in 7-1/2". Those grips would be expected on a gun in the 141xxx +/- range, and are rarely seen. That looks like a S. D. Myers holster.
This is a 45 x 7-1/2" in the 141xxx range. The grips are the so-called "transition" type. The gun was shipped Aug 11, 1892. Down the backstrap is engraved "J. W. Peyton, Jr.". James William Peyton (1874-1942) lived near Rockwall, TX at the time. He later moved to Shreveport, LA where the portrait picture was made in 1917.Please explain about the grips