Sorry about that! I just missed the 4th picture....
Anyway.. I read the serial as "38571
From SCSW 4th issue, you have a Model No. 1 2nd Issue made from 1860 to 1868 in a serial range of 11,612 - 126,361. (117,000 made)
The book values them at $150 Poor, $250 Fair. I don't think yours would exceed these conditions even with a set of correct grips. (Finding grips might be a problem.)
Someone here should know the approximate cut off date for Civil War production. Hopefully they will post. As for an actual date, you will need to get a letter at $75.00. (I don't know if I would spend the money on one in this condition. But, then again, there is always a chance it went to a name instead of just a distributor. Your call....