I use RockAuto for just about everything. In fact, i just bought replacement parts for the entire stearing system on my 1999 K1500.
Tierod ends (inner and outer) idler arm, pitman arm, adjusting sleeves, idler arm bracket, and centerlink! all told, $310 including shipping, and ALL are Moog "problem solvers" series!
Local shop wanted $289 just to replace the Pitman arm ($90 for the part, rest was labor)
*** Also, always always always search for the discount code prior to ordering. it will basically pay for shipping! ***