It depends on a lot of factors, condition, originality, etc. You might also try a site called
www.gunandknife.com . They have a forum devoted especially to the M1 carbine, and some pretty good people who can help better than I. Two divisions of GM made carbines, Saginaw Steering Gear and Inland. Get all the markings, including the barrel markings and pitch it at the carbine guys.
Jim