The best Cobb alternative is an open source tuner and tune. It is highly dependent on your comfort with computers, cables and tuning software but in many cases it places you in more control over your car because you have access to all the options.
Rom raider is a great place to start and the tactrix cable will be needed no matter which tuning software you choose. It lets you interface with the OBD2 over USB.
Honestly your best bet in Australia is to contact a local dyno tuner and have them reflash the ECU for you based on your particular needs. Discuss the options with them ahead of time and make sure they are on the same page as you inregards to reliability vs power output and then after checking them with online reviews you can trust your new baby to them.
hope that helps
Slow is Smooth > Smooth is Fast