I have a bunch of MIDIbox boards and parts that I purchased around 2006. All parts were bought from SmashTV. I had bought enough to make 2 SID engines with an elaborate MIDI controller interface. I also built a custom wood/plexiglass PCB mount which is included along with a bunch of schematic printouts
Below are images of everything. $60 for everything plus shipping based on your location. I can give you my ebay name and business website for reference.
Included Parts:
Soldered:
CoreR4C (Bootstrap V1_2)
SID R3 (no SID chip)
DIN R3
DOUT R3
AIN R3
Unsoldered:
CoreR4C (no chip)
SID R3 (no chip)
(2) DIN R3
DOUT R3
Other:
MBHP LTC R2
LCD V002210 rev C
Bootstrap v1_1b(may not work)
(2) small memory chips
Parts:
(5) MIDI jacks (3 panel-mount, 2 surface-mount)
(10) encoders
(1) pot
(16) small buttons
(4) toggle switches
(1) knob cap
ribbon cable (LCD size)
header pins (male and female)
(20+) black cable connectors
Commodore Parts:
(1) original C64 power supply with separate connector pulled from original machine
(4)2200uf 16V caps
(4)470uf 50V caps
assorted components pulled from original C64 board
Misc:
(1) Wooden/Plastic assembled mount for testing boards (includes MIDI I/O, Power connector, switch, encoders) (2) Large PCB yellow blank sheets
[Partlist.pdf](< base_url >/applications/core/interface/file/attachment.php?id=10902)