Re: 1911 Light Rail
Should be under $100 parts included.
Dawson sometimes runs specials for installation, and offers a great military/le price if you qualify.
Novak is the same as above, and both offer good turn around times. Novak-railed GI style 1911s fit holsters for:
Caspian Recon frames
Wilson CQB/R
Nighthawk railed guns
RRA guns
etc, etc. Everyone using Caspian frames or a similar one. It will fit most Springfield Operator holsters as well so you have a lot of options.
Dawson rail equipped guns fit a number of standard 1911 holsters to include blade-tech and Heinie/Alessi DOJ holsters. There is a lot of info on the 10-8 forums concerning Dawson rail compatibility.
I would recommend one of these two, as the other options out there will not be holster compatible except Surefire. With Surefire's add-on, you are limited to Safariland's tactical holsters.