Bill, ic-racer's post #21 in this thread contains links to a few pages from the Leicina 8s and 8sv service manual. These are both 8/8 cameras. None of the pages is particularly relevant to the OP's major concern, dead motor and dead electronics. They do, though, make the point that there's little in the way of electronics in those cameras.

Ic, even a humble Bell & Howell would do, and the better grade of clockwork B&H cine cameras have good lenses too. I shot with one off and on from '55 to '61, got fine footage. Not, of course, as fine as my father did when he took it to Japan in '53.