I live in much the same type of area you do. Bikes are overpriced, even complete piles of crap are overpriced. Around here, people will sell basketcase Irons that needs a ton of work, for $3000.
As said already, it would be better to find a different cb to cafe. The reason the sohc is used is that it lends itself to the look with minimal work. The dohc has different frame/tank geometry and the look is much harder to achieve. I get the money issue though. I have 2 kids in various activities and it really cramps any thing bike related.
The ride IS the adventure. The destination is just to get gas!