I have done some brake research: The brake caliper and pad for the AE86 is unique (excpt KE71 panel van which has the same rotor and caliper as the sprinter).
There are no pads available for other cars that go into AE86 but there are good pads available. I have some Endless pads, but will not use them due to their harshness on rotors but do have EBC KEVLAR pads. They are just below EBC green stuff. They worked great with solid rotor but did produce alot of brake dust, but there is a trade off for everything. Considering the cost $75, its well worth it. If you are insane and like to waste money (and rotor's) try Endless, Pagid, Lockheed, APRacing, and many other pads. All the big companies still make pads for AE86 as they still race/rally them all over the world.