If the barrel and cylinder s/n fonts are both the same, and of the later style, then I would definitely be leaning towards them both being a later factory replacement........possibly/most likely the refinish happened then as well.

I look at it this way, if you are going to have a caliber converted refinished example it doesn't hurt the value nearly as much to have it be a factory rework job versus being reworked by some unnamed individual.

I think we know most of what happened here but having a Factory letter and a SWHF letter would more exact as to when, who, and original configuration when it shipped as well as any later factory rework performed.