That's actually a "fully-sloping" crown rather than a unicrown. The crown sockets inside of the blades, rather than the other way around on the box crowns we all know and love. With unicrowns fork blades are curved at the top and are welded directly to the steer tube. Forgive the explanation but I'm gearing up to build my own frames and I guess that makes me feel like I have to . I know Cinelli was producing crowns very similar to the one on ebay before investment-casting became a widespread method of production. However, I don't know when they started and if they were available in the early- mid-70s. I can't recall seeing fully-sloping crowns on anything from around that timeframe but that doesn't mean much. Since there are no decals (excepting the 531 of course) and since the headbadge could've been re-riveted a fork replacement/repaint seems like a definate possibility. Also, the frankenbike build may indicate a previous owner who wasn't necessarily as crazy as I am about correctness. The funny thing is that I can't see any obvious signs of it having been repainted so I'm inclined to believe that if it has been, it was a professional job, which wouldn't fit with the frankenbike thing. I guess I'll just sum it up by saying that if I could afford it and if you didn't already have dibs I'd think seriously about picking it up. It looks to be nicely made and the non-Campy parts ought to keep the price reasonable. Yeah, I'm such a big help, huh? -Chris