As of August 2015, good stores to find Chevy Silverado replacement parts are online at JC Whitney and Stillen. The Better Business Bureau gives both retailers A+ ratings, based on how long businesses have operated, the number of BBB complaints filed and the resolution of those grievances.
JC Whitney offers many Silverado replacement parts, such as tailgates, fenders and headlight brackets. Free shipping with no minimum purchase is standard policy. Stillen has multiple pages for the Silverado, including parts for suspensions, brakes, and exterior and interior fixtures. They also have phone numbers for expert advice on cars, trucks and SUVs.