If you're looking for serious volume and low-end tone, try to find an early Takamine jumbo, preferably old enough to have been made in Japan rather than Korea. I think the model is the AN20, or if you want electrics the EN20. I have a 25 year old EN20, and it's a superb guitar. Too loud for sessions, it just overpowers other guitars. (Maybe I could try playing softer????)
Blueridge are very nice, and I think Breedlove are now doing a lower end range that have a sweet tone. A Seagull would be good; I have one of their early 12-strings, and it's a belter; very easy to play for a 12. As an 'oddity' choice, think about importing a Babicz Identity series from the States; a friend has one, and it's very good indeed, if you can live with the weird 'fan' string attachment. The dollar is at a low level, so some shopping around should drop it to within your budget. See one here
.Hope this helps.
Tim