There's a big pile of RCA COSMAC development boards, mounted in rack
chassis, with "many" options (ROMs, memory, LED displays, power
supplies, etc) at the Black Hole in Los Alamos. Aka Los Alamos Sales Co.
I neglected to say some months ago, and it just popped into my head now.
I have the big fat RCA manual. I just have too much stuff ("just one
thin leetle mint sir!").