The seller is parting out a bike, including this frame and fork, late 70s maybe. I've never seen a Colnago like this, but Europe saw models in the 70s that we never saw..
He's selling some nice parts that were once on the frame... seems too bad, but I'm guessing he'll make a lot more on the part-out than he would have selling the whole bike, given the size of the frame, if nothing else.
Charles Andrews
SoCal