You probably won't agree as a matter of principle, but maybe an SW20?
I just picked one up for $2150 and theres nothing wrong with it. It'll fly through a WOF. The 3SGE isn't too bad on gas if you drive it nicely, and its still got a bit of poke when you want it.
But seeing as you're an AW driver, I can assume it'd be your last choice
Also if you're wanting something with a bit of room then it flys straight out the window.
If you're wanting something with 4 doors, then I reckon a Corona would be a safe bet. You'd even have money left over for gas!
Oh, and I misread the title to say "economical reliable computer". Haha
Motorsport is like sex. You could take it to track and have a long, enjoyable session, or you could take it to the strip and get it over with in less than 20 seconds.