Welcome to the Forum. Your revolver would have almost certainly been shipped in 1864. It appears that it has a 6" barrel, but there are some problems to discuss. This Model should have an ejector rod under the barrel to assist in pushing out spend casings from the cylinder. It also looks like the pivot screw has been replaced, maybe to tighen up a loose hinge. The weakest point on a Model 2 design is the hinge, since it would often loosen with use and make the barrel wobble on the frame.
The Model 2 Army, as it was called, was a major advancement in technology, since before its introduction, only cap & ball or small caliber rimfire handguns were available. With the start of production in 1861, this six shooter immediately became very popular as a private purchase gun during the civil war. Production ended in 1874, with over 77,000 made. If you can find 32 rimfire ammunition, these revolvers still shoot great and most are still very accurate.