Here is an original Bartolini TCT preamp. Hard to find MCT mid boost module included, as are volume, MN blend and bass and treble pots. No mid pot but according to this
schematic it takes a 50K pot. I had plans to fit this into a standard 3 pot Jazz plate with a hidden trimpot for the mids and stacked concentric bass/treble. But current finances necessitate selling some unused items.
This is the same pre that Marcus Miller uses and he reportedly seeks out used ones. Here you go Marcus, right here! $80 plus $6 shipping CON US