I have a Polaroid Sprintscan 45i for sale. It scans up to 4x5. It is SCSI, but I use it with no problem on my Mac Pro running OS X 7.5 with Vuescan. I'll throw in the scsi adapter I am using.

Unless you buy the Hasselblad scanners that cover 4x5, this is the best option I have seen. Mine looks new, runs perfect, and is great for scanning anything up to 4x5.

BONUS: it comes with a special holder that has ANR glass on the top and bottom. This holder is simply the best I've used: absolutely no Newton rings at all. Perfectly flat film. It's amazing and I don't even bother using the standard holders (they do come with though).

I'd like to get $450 and if someone is local in the Bay Area that would be ideal.

If interested, please make an offer - I won't be offended.