I have only seen such cables come already attached to
devices.  I think
 you may have to fabricate them.
 Now... what you can do is to make a *double-sided* board and design it
 to be universal.  You'll just be using 50% of its potential. 
I think I may have something like this...though it was originally done for
Posibus.  The DF32 emulator I bought from Charles Morris uses edge connector
cards built by a board shop, and 40-pin (I think) ribbon cables to connect
to the 8L's (bought that, too) Posibus.  Shoudn't be too hard to lay out the
boards starting from there, anyway.  At 11*2=22 boards/device, you are even
talking quantities that make sense to send out to a board fabricator.
BTW: Any market for DF32 emulators out there?  I like mine, but I wondered
if there was demand to get more made?
    Vince