These days, there are MANY options out there for what you seek. I can only speak of what I know. If you come across a used Epifani, they have some single 12's and 15's, with adjustable tweeters, that I really like. I have an UL 112, it's got a neo speaker, nice and light. If you are lucky enough to find a used Phil Jones cabinet, these things are the shiznit. There are a 6 and a 9 speaker cabinet, with these small proprietary speakers, that really kick air. As mentioned, Fearful designs are all the rage now, and deservedly so. There are several builders making them, but they don't turn up used too often. Of course, you can always wander in to your nearest national retailer, and try what they have. GK, Hartke, SWR, are often in the used inventory, and may offer just what you need.