Thanks for the explainations. I just meant something like this: http://www.brownells.com/rifle-parts...-prod1870.aspx
Might be cheaper than buying a new gun (hate to give a reason not to do that though...) and he wouldn't have to cut up his stock.
I've seen a guy put an adjustable comb on his f-class rifle, using a bandsaw and some metal pins. I just couldn't imagine doing that to some of those pretty stocks your guns have.