Hsu and SVS are internet direct companies. However, they have a very liberal return policy. So if you can float a purchase on your credit card for awhile, you can order one of their subs and try it out where it matters the most...your home.
I believe the Depth is right around $2k (their flagship Descent is $2800...I *think*). Anyway, since you're dropping $2k on a subwoofer, Paragon should be nice enough to let you try it out in your home.
Also, for what it's worth, try to find a JL Audio home dealer. I think their 12" Fathom sub is within your budget and would definitely be musical.