I have long been waiting for a Minox C black; this one is in almost mint condition, with its own case. It is an excellent camera, and it is working just marvelous.
According to its serial number, it has been manufactured between 1974 – 1975:
(source: http://www.submin.com/8×11/collection/minox/ )
Camera sports a flat rim, as opposed to the raised rim of older models, a metric distance thumb wheel, and red led. Otherwise, it is identical to a chrome/anodized aluminum C.