Basically you want to find a 2nd hand one mate. I got my GReddy PRofec B for $350 and I reccomend it 100%, total adjustment from the cabin, super easy to use and setup, can adjust spool/holding of boost with the balance control and theres settings on the back you can change if your car has an overboosting problem.
I got mine from a guy I know in Malaysia he has a few others as well
Al