HI there, i just came across this post, i am new to the forum and have just started a rebuild of my 1972 S3 and have the exact same issue in that i have free wheeling hubs but of a completely unknown brand/design! you mentioned a post from 12 years ago which answered your q's, would you mind at all posting that link? I've put a pic of mine below which are also different to yours and despite trawling through pictures online i cannot find any that look like the ones fitted to my series 3.
if anyone else is able to help me out with what they are that would be great.
(P.S. the Geoffrey Croker videos are class)
thanks all
G