There is no reason to get such a large receiver as the RX-Z9 to use it as a pre/pro. It doesn't even have HDMI support, LOL.
I would suggest selling the Sherwood pre/pro as-is on eBay or Audiogon if you can't find or get replacement parts for it, certainly don't throw it away, if you you are going to do that just send it to me so I can play with it, I'll pay shipping.
What sources do you have to connect to a receiver or preamp/processor, and what display will you be using?
A receiver like the Onkyo TX-SR705, Yamaha RX-V1800, Denon AVR-2808CI would all work as great preamp/processors to feed the Outlaw Monoblocks you just ordered.

Integra has a very nice pre/pro out for under $2000 that has awesome HD scaling ability along with every feature you could possibly think of.
IMO, the RX-Z9 is outdated and lacks the features that you might be looking for. It just doesn't fit with your criteria for the money, basically you would be paying for a few extra connections and a monster internal amplifier you wouldn never be using, and not to mention the rack space that tank would consume.
You owe it to yourself to spend less on a pre/pro or receiver and perhaps upgrade your subwoofer with your money saved, you win from basically all fronts.
