You have lots of choices. There are more manufactures than I know, and tons of distributors. Major distributors are Midway (www.midwayusa.com) and Brownells (www.brownells.com).
Ed Brown - http://www.edbrown.com/
10-8 Performance - http://www.10-8performance.com
Wilson Combat - http://www.wilsoncombat.com/
Cylinder & Slide - http://www.cylinder-slide.com/
Caspian Arms - http://www.caspianarms.com/
Les Baer - http://www.lesbaer.com/
I know I am missing some, but this should get you more than enough info to want/need to spend thousands of dollars!!