Best monoblock amps for $2000 used

@markj941 - You're going to need to provide more information to get any informed recommendations. What speakers do you have? Are you looking for tube or solid state amps? What is your room size? What type of music do you prefer? How loud do you want to listen?

I'm curious as to why you want to go for monoblock amps on a limited budget.
Generally, you get more bang for your buck with fewer chassis'.
I would think that $2000 would get you a better stereo amp than monoblock amps. 
$2500 would probably get you a better integrated amp.

The more chassis' you want, the more $$$ you will need to spend.

Go fishing for MFA monoblocks.

Wait until they appear. Be stubborn.

Just checked. Gone the way of the dodo bird. The odd used set used to appear. None around, all in people's systems and not coming out.