relicKING,
If it was my pistol, I would just leave it as is. I would just oil it up to protect what is left of it, and display it in a shadow box. It is, after all, over 150 years old.
It would be interesting to know the history of this pistol. The condition of the cylinder is such that it is not a safe shooter, obviously. The steel Colt used back then was not the best, even though English steel was better than American steel at the time, and could have ruptured with a heavy load in a weak chamber. (When Colt started producing the 1860 Army/1861 Navy models he used a newer process steel which he termed as "silver steel".) The wood is good. The frame screw heads and the load lever/rammer pivot screw head are very nice, but what aggravates me is that often the wedge screw head is in bad shape. There is no need to EVER remove that screw. A tap or two on the right side of the wedge with a wooden or plastic mallet (with the application of some oil in the wedge area) should be sufficient to remove it and the barrel and cylinder. The cylinder bolt stop slots are in good shape and there is not an apparent turn line from bolt drag, so I don't think it was ever fired a great deal.
What is most curious is the "stud" used to secure the load lever to the barrel lug. It definitely is not factory and most probably a later gunsmith repair. Even if you had access to an original screw, the threads are probably gone because the original screw entered from the left side of the barrel lug, and the "stud" may have negated that.
IMO, judging from your pics, it is a 5-shot, 4" barrel 1849 London Pocket .31 caliber, probably made around 1855 due to the long frame/long barrel forcing cone/large beveled load aperture, but without a serial number the date is a guess. If you do not want to state the serial# in this thread, you can PM me and I will look it up and just report back without mentioning the serial number. Some folks are very particular about that.
Even with matching numbers, the "stud" negates any real collector value.
I hope you did not pay a lot for it.
I only collect replicas, being 65 and retired on SS. I have a Replica Arms El Paso 1848 Pocket 6" barrel w/load lever .31 5-shot manufactured in 1963 (first year of production Armi San Marco). Until I can re-temper the bolt/trigger spring, it is just a wall hanger. Note the V-notch load aperture and the short frame/short forcing cone, and the load lever/rammer pivot screw entering from the right side, like the original pistols.
And I have always been a sucker for squareback trigger guards.
Yours is still a nice display pistol. Congrats, sir.
Jim