You might be able to find a VAC Renaissance preamp in that price range. I am impressed by mine. It has the pass through plus you can run single ended or balanced in/outs. The build quality and material quality is second to none. No cheap folded metal case and one of the things I like best, a continous volume control to get the level just right.
The VAC sounds great with my N802's.
The VAC sounds great with my N802's.