JL Billet is now selling the Modular Billet Stock.  The aluminum buttstock is designed to fit all AR-style rifles with a Mil-Spec buffer tube.

By itself, the stock weighs 16 ounces.  Other than the cheek pad and base, no plastic parts are used in the stock.  A variety of colors are available from JL Billet.  MSRP is $249.95.  The company is also selling several accessories for the stock, including a Picatinny rail and a glass breaker.