Mine is from 1967 and at a guess your one may be older. I find it very hard to get through the day without wearing this one for at least an hour or two.
This may be a bit delayed, but I too have one of these; and it's from 1967-it even says so on the dial!
Totally agreed-great pieces!!
Leaving HK but I just found out that I can only drop my Daughter in BKK and then will have to head straight to GZ, BJ and SH before returning to Singapore 馃槣 so will be with this one for almost 2 weeks more.