G'day,
This won't help with your search for the seats, but....
The 3rd row came standard in my Aussie Jackaroo (Trooper).
You may have trouble fitting them after-market (though I stand ready to be corrected!).
Each of the 2 seats has 2 mounting hinges:
the left seat has the forward mount on the wheel-arch and the rear mount in the side of the cabin.
the right seat has both mounts on the wheel-arch.
There is also a 'catch' socket sunk into the luggage floor to receive the seat locks.
Possibly the seat-belt mountings are pre-fitted to all models?
All the best with your quest.
P.S> if you don't have any luck here you could try the folks over on
http://forum.planetisuzoo.com/