Are you wanting to buy the unit and install it yourself or are you wanting someone to do it for you? If your going to DIY, you made need to go to Brownells and buy the installation jigs as well. Trying to mount one without the right tools and jigs will not make a very nice install.
I buy them straight from graco. The last one I bought was $59.95 that has been awhile. I have installed them myself without any jigs etc. with pretty good luck, The only shaky part for me is enlarging the hole in the stock for the adjustment screw. I remove a little at a time checking for clearence etc.
Superump, I am not sure what it is you want. Graco sells an adjustable butt plate (retail $69), they also sell recoil reducers (retail $181 for non-sdjustable LOP and $261 for adj.LOP).
The butt plate does not take any special tooling to install. The recoil reducers do. I have attached pics of the tooling and a couple of sanding jigs I made up to sand the Gracoil and recoil pad together. Bob