You guys know I don't claim to be a truck person in any way, but I do a lot of aftermarket reading. Seems these covers were popular with truck and off-road types:
Wet Okole
Tahoe or suburban covers should fit. Your seats have the same frame and although the foam and leather patterns are slightly different, for purposes of a seat cover it should be close enough .... check out the pics of the 00 Tahoe seats on the site.
Founding member of the "No Hummer Krew"