I recommend fenderworld.com as well. I bought mine off of Ebay through fenderworld for $231. I don't know if they're any more expensive for the older body style, but I would think it would be comparable. I love mine!
White 2007.5 2500HD LT Quad Cab SB, LMM, Automatic, 4x4
Modifications by NOR CAL TRUCK: Cognito 4" Suspension Lift, Cognito Heavy Duty Tie Rods, Bilsteins all the way around, Sulastic Rubber Springs, 52 Gallon Titan Tank, Black XD Revolvers 18x9, 325/60/18 Nitto Terra Grapplers, Autometer Pillar with Phantom Boost and Pyro, Transgo Jr. with Mag Hytec deep pan, EGR Block Plate, BD Exhaust Manifold, Air Lift Air Bags with WirelessAIR, AMP retractable steps (need an updated signature picture) and Nicktane Filter Kit
EFI Live tuned by Idaho Rob
Other Mods: 4" MBRP Exhaust, Mag Hytec rear differential cover and AMSOIL Bypass Filter Kit