That is the Model 1842 pistol, a reliable and well-liked weapon. It is nearly identical with the Model 1836, the last U.S. military flintlock pistol, except that the 1842 uses brass furniture instead of the iron used on the 1836. Some 1842's were undoubtedly used in the Civil War, even though they were obsolete by that time. (Any claimed CW association that would add to the gun's sale price should require documentation.)
I know of no repros, but those pistols are fairly common and relatively inexpensive (under $800 for a shooter). They are well made and if the barrel is in good shape can be fired with no problem. The original projectile was a round lead ball of .537" caliber, issued in paper cartridges which were torn to load the powder and ball then discarded. No patch was used and the cartridge paper was not rammed into the bore. The ball was retained by friction and a fairly tight fit. The cap is the standard musket cap.
While it would be silly to suggest using one as a defense gun, I have little doubt that anyone with evil intent just might find a need to be elsewhere after looking at the muzzles of a pair of .54 pistols, antique or not.
I have used those .54 caliber pre-lubed bullets with good success, though they are heavier than the original balls and the powder charge should be reduced accordingly. Note that unlike the rifle musket, the wide head of the ramrod does not go into the barrel; it is spread out like that to be easy on the hand.
Jim
