Star Trek Next Gen, as well as Data East's Star Trek 25th Anniversary, are both excellent machines.
Both are fun to play. You cant go wrong with either. Pricing in your part of the world is really unknown to us guys in other states.
Contact Mark C and hit him up for a good cash price. He sends pins around the world, so melbourne to Perth wont be a hassle.
**Also, Bigdaddy from our forum is selling a real nice FRANKENSTEIN for only $2350.00. Thats a great machine and in real good nick, ready to plug in and play without any hassles. That would be a smart buy as a first or tenth machine because it has lots of excellent shots, the biggest dot-matrix display of any pinball ever made, and overall is a real nice pin. That would be worth looking into when u find the Star Trek pin pricing to be ALOT more.