I had a 1980 Supra (same car, but with the 6cyl Cressida engine). Here are a couple things to ask about:
1) Check the headgasket thoroughly. The Supra always had headgasket trouble - I replaced two, and it had been done as well before I bought the car.
2) How's the clutch? Not just the clutch plates, but (at least on the Supra) it was a hydraulic unit. I had to replace the actuator unit after it blew warm hydraulic oil all over my right foot.
3) Rear brakes - the Supra's rear disc brakes and parking brake were a mess; some of the worst engineering I've ever seen. Very susceptible to weather damage and rust. This car might have drums which would probably be better.
The Celica/Supra of that age had a solid rear axle, so it was a bit skitterish oin the corners if the paving was rough. The 6cyl Supra was fun to drive and had boarloads of torque; I've driven the 4cyl version as well and it's not bad either. I don't know what used car prices are like in Australia, but go look at it, drive it, and if you like it, offer AU$750 and go from there.
Give it a go, and best of luck to you.
no picture?
