Looks like the AN 12 inch with a Qts of .48 may lack some bass in OB but fits in a monitor sized cab of 24" X 13.5" X 11.25" ( maybe get by with one sheet of plywood? ) which is a nice size to build. It will no doubt sound fantastic in the monitor size enclosure.

At $250 there are other great choices like the two 8 inch Tang Bands (17 and 18 hundreds ) which are cheaper on ebay than Parts Express.