I have what I believe is a early to mid '70s Dura Ace front derailleur that I plan on matching up with the Crane rear-d I have, for a full Dura Ace outfitted bike. The Charles Martin bike I bought this past year came with a bunch of early DA parts, mixed in with some '74 Campy NR and other stuff (early Hi-E hubs, SR crank, Mavic stem, Zeus post), all from the same era. I plan on rebuilding it with all (or most) DA. The head set (steel), calipers, levers, and front-d were all DA. The front-D is very Campy SR-ish in appearance. Steel cage with four slots and "DURA-ACE" engraving. The body and band-clamp are black anodized with the band having "Shimano" cast into the front. Hex-head (not hex-socket) cable and band clamp bolts. The calipers, levers and HS that were hung on the frame all appear to be first-gen DA, so this front-D may be as well.
I can send or post pics (PhotoPoint), if anyone is interested in seeing what the FD looks like.
Wayne Bingham
Falls Church VA