Ion is out, RockBandParts.com has some stock left (when I made this post I was under the impression they were out) There's one ebay listing from Hong Kong ($100 + weeks in shipping).
Are there alternatives, if not, that can make use of my Ion kit (third party brains that hook into the PS3, etc?).
What do I do with a failing Ion next time? Any non-Ion brain that's cheap and can be combined with the Madcatz MIDI adapter?