Also one of these would cost a month's worth of wages. I suspect some amount of care was taken of them.
To each their own, but I personally would not go for the "weathered" look unless I was trying to make a display piece as some kind of decoration or prop. Or if you want to pretend you are shooting a 150-year-old original.
If you are wanting to experience what it was like shooting them 150 years ago, well, it would feel like shooting a nice, new gun!
Steve