just walk into your local chevy dealer, write down on a piece of paper, every thing you want , body style color, gear ratio, engine, driveline. ask to talk to a salesman. give him your search criteria and business card and tell him you want it with in 7 days. and you'll even finance it thru the dealer if he likes. . you'll have your NEW truck for $30,000 with bells and whistles. and that's how it done. you should be $10,000 off MSRP. why waste your time with a used Gov. truck with 100k on it. for $20k that's nuts. the new trucks are not flying off the lots.
if you find one with 3.74 rear end , those are even cheaper cause it's percieved poor fuel economy