Dom, Steve used to make a little guitar amp, I bet he still could assist if you contacted him. Basically a Zen amp in his cabinet.
Personally I totally understand the love of that tube bass amp. I have a '59 Bassman LTD Reissue and it's great. But to be honest I now use two other amps that surprisingly I like more and they are not all tube. One is a Fender TV Bassman Fifteen. Tremendous solid state (perhaps Class D?) amp with a 12AU7 preamp. Honest to gosh it has so much depth and texture and sounds like the worlds quietest powerful tube amp. The other is my jazz guitar amp, a Fender Jazzmaster Ultralight SE that I have that only has a clean channel (shop I got it from says it was a prototype, also had a special wine finish. This devil is light (separate head and cabinet) and rich and again totally quiet but tube-like, and there's no tube inside. . . . Shocks me that they are my preferred amps.
If you don't want to DYI these are worth seeking out (discontinued now).

Haven't found my photo of the Jazzmaster Ultralight yet.