1860 Army Richards Conversion

Hi, I'm looking for some assistance regarding an 1860 Army Richards Conversion. The serial numbers are as follows: 188784 barrel (mfg.1870), 191554
frame (mfg. 1871), 554 wedge, 1554 cylinder, 191554 trigger guard, and 191554 backstrap. It appears that the conversion barrel was replaced with a standard 1860 Army barrel, unless some were sold without the conversion. Also, there is no patent date, just "Colt's Patent" on the left side of the frame. I don't see any engraving on the cylinder, either. Colt said they have no information on conversion models. Any information or comments you could provide would be appreciated! If I can figure out how to insert some images, I'll add a few photos. Thanks