Welcome to the site! A co-worker of mine had an 89 Silverado 4x4 with 480,000km (297,000mi) on it, just sold it a couple months ago for $5000. The thing looked like brand new. Low miles on the 355ci, 700r4. VERY well taken care of, fresh body/paint job. 17" Escalade wheels, the thing looked/ran like brand new.
I work at a GM dealer so a I see some high mileage vehicles come in! The one that sticks out the most is a guy that has a 1994 K2500 Suburban 454 that's just about to roll 600,000km (372,000mi). Original motor and trans, runs like a champ and looks great!
2000 Chevy Silverado RCSB LS6 5 speed, LS6 short block, 317 heads, LS6 intake, Lunati 220/224 .575/.575 112LSA cam, Edelbrock Headers, CTS-V accessory drive, Nelson Performance Custom Tune.