Sold by Nazar on the FJCruiserForums.com site - company is Wicked CAS. You can buy the starter setup for about what you can sell a stock box/sub on Ebay for ....
Variety of configurations. One tenth inch, two ten inch, and a 12 option.
Not self-amped, but you can put an amp under the passenger seat. I'm gonna to run a JL 500/1 mono amp and two JL W3 10" subs. Then a 300/4 to power the other speakers (replaced with Infinitely, Focals, DBs). Putting an amp under the seat means you sacrifice the heat venting to the rear. I don't care about that though.