FWIW, those guns were not rebarrelled, the barrel was simply cut off and crowned and a new sight put on. That eliminated the lock at the end of the extractor rod, but was OK for light use. A lot of that work was done in England, by Cogswell & Harrison, which was owned at that time by Interarmco (later Interarms).
The plating and grips are not original and were probably done after the "chopped" gun was imported into the U.S.
Jim