Ascend subwoofer
 

I have read, good feedback on Ascends 15 inch sub. (Rythmik, direct servo)

Granted its not an F113! But the price point is in the sweek spot of a new Viking toaster.

(I purchased Inexpensive Sierra-1's from them, that blew me away, like the reviews predicted)

Edit: "Ivans big May sale hooked and closed me!"
Sorry Ascend's Rythmik...