here's an idea... take a working holiday in the UK for 12 months. By a lotus elise... series 1 versions from the late 90's - early 2000's sell for around 7000 pounds (sometimes you find them for as low as 4000 pounds).
At the current exchange rate, you get them for around 14.5k AUD. Bring it back as a personal import
When the rover engine dies, slam in whatever nissan motor you want.

You may also be able to do the same thing by taking a working holiday in Japan, although I have no idea what they cost there.