Yes I have found this type of ECU for sale in the EU, I bought one last week from an ebay seller in eastern europe. I got one last week for £60 inc shipping and taxes from Lithuania. They are not that common, but also they are not expensive.
COROLLA (_E12_). Part number. Vehicle information All of our parts are GENUINE! Item information Item condition.
www.ebay.co.uk
I have also found a Corolla 1.6 VVTi ecu which is fundamentally the same, but I cannot write this flash data to it because they use a "password" to check the right firmware is going on the right ECU, and I cannot find a factory update file for the 1.6 ecu.
UK Corolla uses the later ECU type, which is why over here they are not good donors for the 2zz swap, but I am no expert in any of that, nor do I have a car to confirm. But not all Corolla's here in the UK are are equal, some were made in France, some Japan and some in the UK, but again I'm no corolla expert.
In an MR2, the Climate control panel has a few wires that goes to the cluster.Two is for AC demand, one is for rear window heater, two go to a thermistor in the duct work under the dash. But again, my car is non-AC so doesn't seem to have all the wires populated, so I cannot confirm this. See wiring diagram attached.
Someone on board who can "sniff the bean" for the AC would be very helpful. All you need is an arduino, and make the two circuits on the left up from here
Toyota's Bean Multiplex Communication Protocol for Arduino - BeanMPX/bean-mpx_circuit.png at master · fiztech-code/BeanMPX
github.com
Then you can push the 12v, GND, TX and RX wires into the back of your clusters connectors and use the Arduino serial monitor window to stream the bean while you press the AC buttons.
The circuit boards that are getting delivered this week have all the electronics on the board for the AC to work, it just needs the Arduino coding to listen to the packets from the cluster and then fire the correct digital outputs.