Are you putting on a non-military barrel as a replacement for the 1942?

As far as value it depends on the condition of the bore and how much wear. If you have access to some sort of muzzle gauge, that would be helpful. If worse to worse, you can use an M2-type 30-06 cartridge (the nose inserted in the muzzle, not chambered!) to get a rough idea as to wear. Obviously, the condition of the bore (lack or presence of any pitting) would be of interest to a potential buyer.

If a good bore and a fair amount of "life" left, the value would be in the $135-200 range. The lesser the wear, the more towards the "high" end.