SN 77794, marked Mamiyaflex on top. It seems to be older then C1 model. 

Camera looks good. The only problem it has, that it is missing leatherette. What is left of it, is very dry and brittle. So most of the outer leatherette is missing or gone. I don't see any other problems. Winding is smooth. Bellows look very nice, they don't leak light. Camera needs lens and a finder. Please note that C220, C330 finders will not fit this camera. You have to get older finders. 

Please look at the pictures for more info.