Just thought I'd chip in, someone around here has tried st185 calipers, so I imagine ST184s wouldn't be far off, and being newer, probably more efficient.
Also, remember the ST162 weighs about 1150kgs (dry) so it doesn't need huge brakes. If you go to enough importers someone will have the ST165 twin-pot (or maybe elusive four-pot) calipers lying around the place. Grab yourself some slotted rotors and you should have enough braking for even a pretty hot ST162.
I hear the Camry calipers are a pretty close match too but you should go to a wreckers and compare.