I've had many B&K amps and you can't go wrong with them - especially in your budget range. I've also had several Parasound amps and agree with Tommy - the HCA1000 is a good option and can be found in your range. I find the B&K amps to be a little more natural sounding, primarily because the Parasounds have a little bit of punchiness in the bass, although this characteristic is attractive with the right speakers.
The build quality of both B&K and Parasound is fantastic.
The build quality of both B&K and Parasound is fantastic.