Sideshow,
My EPC also says 'not applicable ' but it only lists JDM, so looking at their numbers, the AE82 ECU's range from -12010 to -12110.
The AE92 units run from -12180 to -12450.
It probably unlikely, but you may have an Aust spec ECU from an SX AE92 which is why I have no listing for the thing.
Like what's been said above, try calling a Toyota dealer parts dept. and quote them the number you have and see what they say..
Cheers,
Mitch.