A month later and he is still asking for $430.00. I really don't think he'll get it.
Especially since an important part is missing, the cable that plugs into that odd socket. On the other end of that cable should be a key switch (that is, a lock cylinder with electrical contacts), mounted on a narrow strip of sheet metal that would in turn be mounted on the 19" equipment rack of a C3-B or C3-C, just under the floppy drives and above the CPU. The switch had four positions: off, CPU only on, CPU and floppies on, and all on (CPU, floppies, and hard drive). The whole thing was typically called a "power sequencer", as it ensured that power would be sequenced on and off in the correct order to avoid damage to data.
No current OSI hardware
Former programmer for Dwo Quong Fok Lok Sow and Orion Software Associates
Former owner of C1P MF (original version) and C2-8P DF (502-based)