Modular Synth Panels

I have this really cool EML 301 controller that has a joystick, filter
and a pitch knob matrix (that does other stuff)

http://www.sequencer.de/pix/eml/eml-400.jpg

The really cool part is: There is a matrix of 12 knobs on the panel,
each knob is triggered by a telephone/calculator type membrane keypad.
You set the pitch and press the number and get a fixed pitch output. I
would suppose it could also be output of various types, cv, selected
waveforms.  A set and forget control for a modular.

I am thinking this would make a nice composing and performance module.
 I can't copy the EML circuitry because it is not to a modern
standard, weird scale and 1st gen op amps.

Any help available, any interest ?