Greetings from Finland I´m vintage watch enthusiast (mainly from ´70s watch) and now my first Heuer (Carrera ref. 150.573F) is arriving. While waiting I´m looking for all kind of information about it and I´m checking out age of this ref. Seller thought that it is from year 1969 but I´ve found that cal 15 came in 1972 and barrel case came in 1974. And somewhere I saw that cal 15 disappeared from Carrera after 1974. So can anyone wiser confirmed that is this ref. from 1974? Or is there somewhere serial number list on web I can check out age of this Heuer after I got it?