The company Wargames Factory, which makes plastic miniatures, has a new
program where people suggest sprues for them to make, and if there is
enough interest they will produce them.
One of the possibilities is 10mm American Civil War basic infantry. If
they get enough pre-orders for them, they will make them. Check it
out, and place a pre-order if you're interested.
http://www.wargamesfactory.com/league_acw