PSU's are going to be annoying, since these things take custom power. Unless you have the wiring harness and the PDU's for the enclosures, finding something that'll work will be tough.
I think you are gonna have to do some legwork if you wanna offload these.
Specially if you plan on profiting off free parts.
Edit: per the manual... it requires 2x ATX 20pin power connectors.
That is gonna be ugly...
The two power headers are for redundant power, that's all. Not a big deal. It will run with one. But...
Take a GOOD look at that wiring diagram in the manual - they may be ATX 20-pin connectors, but it's absolutely NOT an ATX format. There's 3 or 4 sets of 4 wire 12v+GND in that header, and absolutely NO 5v (edit: there is ONE pin with +5v). That board will not run off any standard PSU, which is why the Asus website says "Custom Power Supply Required".
I had already looked into these a couple weeks ago because I found a super cheap source to buy a handful of them. I ended up not doing so specifically because it meant either buying the entire enclosure to make them work or modding the crap out of a power supply and praying I don't blow something up in the process.
so it turns out you can get the board to turn on by jamming a pair of EPS12V ("8-pin CPU") connectors into the power connector (make sure to get the polarity right!)
or rather, the lights light up - I lack a CPU so I can't completely verify that the board is happy, but it bodes well...
If anyone is looking to buy 'em, I'd take $2k + shipping for the lot, if you want fewer we can work something out over PM (say $500 for 4).