It's a 2007 according to a couple of pics I've been able to find. Dura-Ace RD-7800 was 2004-2008 so that makes sense. Top tube is slightly too long for me but a shorter stem would pretty much solve that if I were to keep it. It probably is a 56 or so (I ride 52cm). I'd never come close to standing over a 56cm classic frame and the saddle would need to be slammed all the way down, but this one I can because of the sloping top tube.
Better pic with saddle adjusted for me:
