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On the bass amp tip, a lot of outboard bass preamps from Sadowsky et al. are basically mildly adapted versions of the blackface Fender preamp, just switching tubes to transistors (often jfets) and scaling the eq circuits to go with the transistor characteristics. If you don't need an overdriven sound from the preamp or to overdrive it, sending one of those to a line-in or loop return on a cheap amp might do very well. The drive might not even suck, but would probably not be as authentic as the sparkly clean stuff.

(There's a big thread on freestompboxes.org on active bass preamp circuits, with some discussion of what circuits are Fender derived. There are some schematics and layouts to build your own, and some sorting of what to look for if you just want the tip of what commercial product to buy.)

I wanted to come in here to second the Peavey Classic 50, but knowing your penchant for volume you can try to track down a classic 100. Also, you could look for Carvin x100b. Company is based in California so maybe some made their way to Oz. could potentially even buy one new, direct through carvin for a good rate. Also, maybe check in with Corey Y, he was looking to sell his awhile ago.

100 watts, super clean, takes pedals like a champ and dirt cheap? Sounds like you want a Yamaha G-100 or B-100 head. Jazz guys swear by the warm, clean Fender-ish sound of the G-100. I have a B-100 and if you don't care about having reverb built into the amp it might be the way to go. Especially if you were looking for a bass amp anyway.