T-Mar thank you for the detailed reply and expert sleuthing! i agree on the repaint for the reasons you mentioned, plus overall, it's very clean - too clean for a bike from 1977! Also, the fact that the paint obscures the serial number would also indicate that it's not original. I think your opinion is the best I'm going to get, so I'm happy to hear it's a higher-echelon model. I will pull the seatpost and measure the wall thickness - perhaps it will actually fit a 27.2mm post.