1978 (gloss and matte examples, 1964 and 1957/59. There's also a 1956 that has a rounded end of the ferrule (not pressed like these all are). I'm missing one of those.
If you find one with the head pinned on at the top of the ferrule send it to me and I'll give you a $50 reward. ;-)
Here's the pinned, the 1956 and the 1957/59 (depending who you talk to).
And, a shocker to some, Zwickey made Bear's first heads.
(And Ben Pearson made Howard Hill's first version heads and bows!)