I'm not sure of the s/n cutoff, but if you're worried about the build date with respect to the A/C, look at the A/C controls on the center consol. The later A/C has a button that says "ACoff" with a LED light on it, the original system had a different button that said "EC" for economy I guess. When they upgraded my system, it included changing out this button too.
I paid 64K for mine with 20K on it but it has a bunch of options. It is also in near-new shape, new tires, etc. I saw a bunch of cars here in Dallas fresh off lease with no options including no CD changer. I guess many people wanted to get into the car as cheaply as possible. I am also very picky about paint and interior damage. Most cars except silver had paint damage, some extensive, that many people would accept but not me. I do know prices have come down a lot but I'm not sure of the current market.
I also looked at an '01 that was identical to the one I bought but no rear A/C and it had the automatic trunk (not available in '00). The car was essentially the same though with the same miles and they wanted about 8K more and it wasn't at a dealer (no Starmark). Same car as I bought so not worth the extra money. They've changed very little until the '03 upgrade.
I wanted a Starmarked car to get peace of mind. Its still under the original warranty to 50K miles so that might be enough, just depends on your aversion to risk.