I should add, my preference is for tubed preamps
There's really excellent synergy between pieces of Atma-Sphere gear. A used MP-3 linestage unit might show up within striking distance of your price range. Then when your piggy bank recovers, there are some worthwhile factory upgrades that can be done (in particular to the power supply). I'd suggest hanging on to the BAT until you are able to make the move to an MP-3.