I think the fork was modified. Possibly to fit smaller diameter wheels, 26" or 650's. From the foil seat tube graphic the frame is probably from the earlier 70's. Looks like possibly Durifort fork tubing, a middle range bike.
The fork although without head set at the moment if fit up the top tube would probably be declining toward the front, another tip off that the fork was raked more. I would carefully check the chrome on the fork blades for stress, chrome in general does not like to be stretched and compressed that much.
I would be reluctant to bend the fork back to level the top tube, three cold settings is not the best practice.