Subaru Rosebery have quoted $352.40 per remote. I almost choked when they told me that. What a joke.

Welcome to ozlib mate.
Not sure what the going rate for an alarm/immobiliser system is but it might be worth checking out as they come with remote central locking which works better than your stock one anyway.
The earlier libs (up until early 2001) had infrared central locking so the key had to be in line-of-sight from the sensor. Hardly worth spending that much money on.

Thanks guys, I'll take a look at both aftermarket alarms and importmonster