Thanks again guys, I really appreciate all your input and I'm slowly but diligently researching your suggestions.
Fikealox, if you're in Australia, you could go with Devries Custom Guitars right?
Haha, he's been suspiciously quiet lately. I wouldn't be surprised if he's working on a new line.
Hey you could also add to your list Ulbrick, Aussie amps that sound great and are well made.
It's funny you should mention them, actually, because it was a Firebottle 5W demo that got me started with all of this. Unfortunately, I've been told the Firebottle might not do what I want, and the rest of their line is out of my price-range:( Ulbrick has stopped production of amps, btw!
I've found it really hard to judge amps from their demo videos tonight; it seems that all of these sort of amps are demoed with bright, bitey, jangly tones - so the breakup is a crisp "rasp", when I'd much prefer a rumbly "growl".I realise in a lot of cases it'd be possible to EQ to my preference, but it makes it really hard for me to get anything useful from the clips.