I have had a IIIC Post war , I think this serial number indicates 1946 or 1947. Its a wonderful camera and sharkskin is delightful to hold . Very fast to street photography and viewfinder and shutter is legendary.
When you hold it with one hand , it stops absolutely horizontal in your hand. You can cock the shutter with your second right hand finger with moving your finger tangential to the screw. Hold the camera , move your right hand second finger parallel to the right side cylinder and all is ready. I learned from one of the Master of Leica , Magnum photographer Ara Güler.