I have finally finished the necessary PCBs and sent them to Olimex for production. Big thanks to the teams making Gschem and PCB for Linux, without them I would not be able to produce the 320mm wide keyboard PCB.
I've created and ordered three PCBS:
1) The main keyboard (steps, tempo, edit, instrument select)
2) The keypad
3) A new output board, including a headphone amp.
The total price for the PCBs, including shipping, is $193,20