It sounds like a early #3 Ballard before they began using lighter weight barrels. As an early #3 it should be a flat top receiver the first had, and not the concave top receiver that came later. The low serial number, and JM Marling address indicates it's probably around 1876-77 period.
The "P" is likely a damaged rollstamp, that had an "R" but the leg broke off, and the workers didn't notice it. Or maybe did, but were waiting for a new rollstamp to be made, and kept using it. Bet there's others out there around the same serial number with the same defect.

I am not sure of downloading it, but "Ballard, the Great American Single Shot Rifle" by John Dutcher is By far the best. It is out of print and hard to find, but if you are persistent you can find one. Perhaps putting a want to buy here might turn one up.

I agree with John Dutcher's book being the end all for Ballard references. Nothing else even comes close to what John put together, and as far as I'm concerned it's one of the best written gun books of all.
I occasionally see a copy selling here at ASSRA in the for sale section, and they're more fairly priced at $130-$150 when they do. I doubt those asking $300-$400 are selling at all. 

I got images of "Bikes" Ballard #3 and it's a nice gun with a special order shotgun buttplate, like those sent to Europe usually had. It's a flat top early receiver, but not a heavy barrel. It's the standard barrel with the tulip at the receiver, as used on all later #3 Ballard rifles.

bikes wrote on Aug 6^th, 2021 at 11:42am:


Sorry, but didn't keep the email with pics. If you want to send the pics again I can load them to Imgur and post them here.
If a copy of Dutcher's book shows up here, and the price is good, by the time someone notified you it would likely be long gone. Best to do as was recommended and post a "want to buy" ad in the "for sale" section to see if anyone responds.

I got my 1st Ballard years ago. The best reference at the time was the museum catalog for The Nunnemacher Collection. Dutcher's book is now the way to go. (You need to Login or Register to view media files and links)