You know any reputable national dealers or refurbished ones? Just googling gives an impressive array of sellers, many of whom have tons of negative reviews that I have no idea are real of fake. Also, I'm 5'8", so I'd think a B, but no basis on which to judge. Edit: also I just realized this is a really old thread. I Hubski searched "Aeron" to pick up a conversation from the other day, and just clicked the first link!
When this thread was new, the answer was "Sit4Less" which then became "Sit4life" which has since gone under. Here's the thing, though: the parts are readily available. The repairs are eminently accomplishable. The hardest thing you can do is replace the hydraulic ram, which I've done, which involves a big badass pair of vice grips and a hammer.
I will bet there's a healthy secondary market in aeron chairs wherever you are. Check craigslist. Imagine if a Saturn station wagon had 55 parts, none of which were in motion with any regularity. How long would they last? And how much of an aftermarket would there be in keeping them functional, especially if Saturn freely sold replacement parts to anyone who wanted them? The part that wears out is the pellicle. Used to be you could buy the fabric and redo it but now you just buy replacement seat pans.