Howdy Flint,
That's some interesting info about the Rem Navy.
I've heard that the Armi San Paolo/Euroarms Rem Navy is the smallest of the Rem Navy replicas, and pretty close to the size of the original Navies. I have an older Armi San Paolo Rem Navy, and after reading your post , I got it out and measured the percussion cylinder (I don't have a conversion cyl. for it) ,...it's 1.608" dia.,....making it closer in size to the Kirst.
That's interesting,...maybe it's just the gripframe on the ASPs that makes them feel similar in size to the originals.
It's great that you have an oportunity to handle, check out and measure an original....
Thanks for sharing that info ,...and the photos are great!