Amazon has Dayton Audio Sub-1500 for $175 + free shipping
Enormous 15" heavy-duty, long-throw woofer
150W amplifier with selectable auto-on feature for satisfying power
Downward-firing flared port design for clean, powerful bass
Perfect for large home theater rooms
Unobtrusive texture black vinyl finish cabinet with removable grill
I have only been in the market for a few weeks, but this is the lowest I've seen it in that time, currently listed at $198 on parts express.