(Preferably in Sydney)

Can they test the MAF as well?
What are the costs?
If its faulty can they fix it?

In all honesty, I think you're between a rock a hard place. I'd suggest an electronic instrument place or an EFI specialist or similar.
There is a place in Marayong called Mobile Instrument Services (MIS), least thats the name I remember. He restores and recalibrates instruments but also does some electronic stuff. I'd suggest talking to him first.
Before you talk to anyone make sure you have a copy of the circuit diagram of the ECU and loom and as much info on the ECU and sensors as possible. Most of it should be available on the web now. Yanks love FI.