Can you do any work yourself?
If so, buy 5 of these at $390 a pair and be in heaven.
Thats if you can go with an overall depth around 4", in a 5l box they can play to the 80s and are fantastic speakers.
http://www.ejjordan.co.uk/drivers/jx92.html
If that depth is too much:
http://www.ejjordan.co.uk/drivers/jxr6.html
4l at about 2" dept will get you down to 100hz and these play all the way upto 30khz!!
With a good sub you would have a full range system that takes up almost no space at all.
I have written a review of my Jordan full range in the review thread, mine are in a sealed 5.2l enclosure and I am using the bigger 4.5" model, not the 2"