Need a bass amp

I am looking to upgrade My homebrew subwoofers.They currently house a pair of Dayton plate-amps@250w with dual 10s per side.
The amp/amps must have balanced and unbalanced inputs (for cabling options),be at least 200W/8 ohm and not break ones' back to lift.
It will be fed off of a Pass Labs XVR-1 crossover.Top-end is a set of Kef LS-50s being driven by Red Dragon Leviathon SE.
Budget is approximately $2000USD.
Thanks in advance for the assistance.
Hypex 800W Amplifier

Best of luck

Peter/PBN, Wouldn't I be better off buying a class D amp:Red Dragon/Hypex/Bel Canto/Nuforce? It seems that much of the circuitry is duplicated and changing the cutout would ruin the cabinet.
IMHO,i believe that the power supplies of one of these units will be superior to the $600 Hypex unit. ?
Have considered a Pass X150/250,,Boulder 250AE monos and Red Dragon 1000-2s.Would a stratos/odessey amp be worth consideration?Looked for the symphonic RG4s but only available overseas.Anything I missed-BC?
The Dayton 250W amp is apx 250MM square the Hypex is apx 267MM square so if you have the room and can make the slightly large cutout you should be fine. The PS unit in the Hypex is very well engineered and thought out and for bass only it would be on the top of my list for a Bass only amplifier, in addition it offers a lot of adjustability options too which surely is a nice feature for a subwoofer amplifier.

Best of Luck

Look at the Crown XLS DriveCore series, clean classD power at bargain prices.