David, all the gunsmiths mentioned are good for your needs, but i thought i would add one more. Depending on where you are possible other needs besides just an installation of a comb, I want you to know Ken Rucker at SpeedBump Stockworks would also do you well. He is located in Sadler, Texas (I have included a link to his site and blog in the website area below my e-mail), but right now he is set-up at his vendors space at the National Shoting Complex in San Antonio, Texas for the World English Sporting Clays shoot that is starting today. He has developed a couple of new recoil reduction systems and they are worth a look. Just thought i would add my $0.02 worth.
Just to make the guys mentioned above look good, send it to me and i'll screw it up real good and then you'll realize how good their work really is. Hell i just put a new blade on my hacksaw and i've got my rasp ready to finnish it up. I'll put some wing nuts on the comb bolts for easy adjustment.---Matt