This Pedal is currently available.
Electro Harmonix Mig 50 in a pedal
Preamp in a pedal of a classic 90’s tube amp. JFETs replace 12AX7 preamp tubes in this faithful recreation of an iconic rock and roll preamp circuit
https://www.acornamps.com/gear/transistor-migfet-50p-preamp
Acorn Amplifiers Transistor MIGFET 50P
Acorn Amplifiers - Transistor MIGFET