Found this on one of my trawls through cyberspace..some great hints here! (I am doing a split prewar style stock at the moment, and this has given me the idea of taking a small piece of wood from under the butt plate, to repair the crack so as to get a wood match.........this guy just saves old wood to the same effect!

http://www.woodworkforums.com/showthread.php?t=8245