if i was in the same situation in you i would be considering the following options.
1: as you said above cams, quads compression etc. lots of money but lots of fun. But how reliable?
or
2.the sr20ve

I would investigate the sr20ve more. They work exactly the same way as honda's vtec, i.e. two cam lobes. They make about 190hp at the fly standard and have a rev limit of 8200. A custom bell housing would be required as well as a custom plenum and headers as they only came in fwd. but in the us guys are making close to 200 hp at the wheels (FWD) with sr16ve cams, headers and chipped ecu and the limit extended to 8500. If you kept it standard you would be pretty close to your hp goal and it would have factory reliability. Downsides are there aren't alot of hot up parts. (but do you need them?)
the solenoid for the cam lobe switching is on the gearbox side of the head (i.e the back)
the custom parts required may cost a fair bit
and of course the fact that bugger all people have converted sr20ve's to rwd so you would have to learn as you go.
Also i have absolutely no idea how much a sr20ve would cost in oz, that alone might blow the $5000

Basically i just want to see someone do a rwd sr20ve since i don't have the stamina to see it through

just my thoughts
Nick