MUCH cheaper to just get an 84M Montana and cut it down. Heck you can get it lighter than the Adirondack and still save a few hundred bucks if you really wanted to go lightweight. However, you can likely save well over $500 just finding a 84M and cutting it down to 20" and not have the stupid colored stock.
My Kimber Montana .308 with 20" barrel and some other things done to put it on a diet. 4 pounds 13 oz naked, and 5.5 pounds with a scope.