The Tascam PS-520!!
... is a hard-to-find item, on it's own. I've seen only one auctioned off by itself, in the last 3 or 4 years.
Late last year, I bought an M520, and it came with the board & supply, but no umbilical power cable!! That's now "project gear" that has seen no use or utility, and will remain boxed up in the garage, until further notice, or until I get it together enough to fabricate the 20 pin power cable, myself!
It also came less [21] 2p jumper plugs, that I've collated a bunch of 6" RCA patch cables, to replace. All-in-all, it was a misrepresented Ebay ripoff, but I successfully did a charge back against Visa and Paypal, and ended up getting the whole mess for net-zero! That's the only good part of this story.
Good luck getting your supply, dude!