I've a set of old cottered cranks somewhere in the spares box, one of several I got when doing up a '62 Freddie Grubb - not sure of the age, but definitely not modern. Will go digging later today and try and get some pictures/measurements.
Just found them - pictures below...crank length is only 165mm c-to-c (never measured them before) - 48t ring. The chrome is worn on the drive side crank, and a little on the non-drive side - both the usual heel rub. I've never even fitted them - had some others that I used.