I think that the Sumo Athena, whose manufacturer is now defunct will give you the best bang for the money. It has a class A output stage that was once highly regarded by Stereophile as the "Preamp for CDs." It has nice and slim styling with record output switching and tons of connections. It was the first preamp I bought and still keep around...used to cost about $600 but I think you can find them for about $175-250. You will not regret it and it comes with rack mounting extensions built it, heavy anonized black aluminum.
Rack mount preamps for cheap
So I have about had it up to there with my Carver Ct-26v A great preamp but only when it decides to work. I'm looking for something under $500 used or new that sounds like the Carver (giant bass and sounds ok at lower volume levels) and it needs to actually be rack mountable, not just look like it's rackmountable (ala the carver). A 1 rack space unit would be ideal. Currently it's mated to my home studio system which has a Peavey 400CS (don't laugh, it sounds good) and some Alesis Monitor 2's I don't really need a phono section at the moment, but the upgrade path would be nice.