First thing is look at the date on the barrel. If the barrel is a replacement barrel that is not within 3 months roughly of the date of manufacture of the reciever I would just put a WW2 rebuilt stock on it or usgi walnut stock of any manufacturer because the barrel is probably a replacement barrel. Basically for a ww2 rebuild stock that's a ww2 stock that either has rebuild marks or has had the original inspector stamp/cartouche sanded off during rebuild. Original ww2 stocks with unsanded cartouche are quite pricey and in my opinion unnecessary expense for this rifle ( to each their own). Really, if it's a mixmaster any USGI walnut stock is just fine. If it's got an original barrel and some other stuff you could theoretically restore it, but that's pricey in its own right, some people regard that as changing the rifle's history, and you would want to do research and make sure it's a rifle you would consider worth restoring. I know rattled a hornets nest bringing up a restoration. Really, the stock is fine as is to shoot but if it bugs you I would just buy a usgi walnut stock or a ww2 stock that's been through a rebuild. I may have missed some things and caused more questions than I answered but happy to help.