Audio Note and Audio Note Kits L3 with upgrades built in like this one with upgraded transformers, volume control, wiring, and capacitors.
https://www.usaudiomart.com/details/649444090-audio-note-ank-l3-pre-amp/This is the personal unit of the ANK US Rep and was professionally built.
Supratek makes some very good preamps as well.
https://www.usaudiomart.com/details/649444090-audio-note-ank-l3-pre-amp/This is the personal unit of the ANK US Rep and was professionally built.
Supratek makes some very good preamps as well.