I've been on the hunt for a modern preamp as well and have been leaning in the tube/hybrid direction. Here are some modern ideas in that price range. All are under 6k MSRP.
- PS Audio BHK
- Rogue Audio RP-7
- Linear Tube Audio MicroZOTL preamp
- Backert Labs Rhumba 1.3
- Primaluna EVO 400 Preamp