Plenty of info on the net to find out if the serial number falls into the serial number range. Almost impossible to give an estimate on value without seeing the gun in person. Check the serial number on the slide behind the firing pin stop to see if both frame and slide are matching. Good place to start. So many were reworked before and during WW2 that it is difficult to tell just what you have. If it is a true "Black Army" 1911 in decent shape, then you are talking possibly in the $2000 and up category, and possibly much more. I'd take it to someone in your area that knows 1911's well, and you have to be careful. I took a 1943 Lend Lease Colt to an "expert" to have him look at it. He told me I had a Colt slide on a RR frame. At that point I knew he was full of it because he didn't even know about the serial number overlap between Colt and RR. What he didn't know is that I had already checked the number behind the firing pin stop and they matched. He couldn't explain the GHD inspector marks on the frame either, which was a Colt inspector mark. Needless to say, be wary. Of course the "expert" I went to see offered me $650 for the pistol, which was a fourth of what it was actually worth.