I recently purchased a cased tintype of an armed soldier. The soldier is wearing a pith helmet, a jacket that looks like something out of a Wild West show, a belt buckle that says US on it, the trousers appear to have a Marine Corps blood stripe down the leg, and is armed with what appears to be a percussion cap rifle with bayonet. I'm going to assume this is post-civil-war. Whatever it is, it's highly confusing.
Any help identifying the unit and the time frame would be greatly appreciated.

Any help identifying the unit and the time frame would be greatly appreciated.

