The OEM carpeted bed with simulated wood grain strips is really tough to locate, not available at this time from GM.
Best bet is watching salvage yards.
Same goes with chrome kits - parts are available here and there - could check with BYERS, RSSRTOY, Doug Allen (Parts Exchange Thread) salvage yards and watch ebay.
"Such are the Vagaries of Life"
Ah, I'm Just Truckin' With Ya!