Putting a date on these is not so easy as Arbiter didn't re-stock pots all too often in the early days.
We
think that the ones with the bolder logo like the one you scored are the earliest ones. They come with pots dated between September and December of 1966. But so do a lot of the ones with the thinner logo. They used those pots for quite a long time. After 12-6 the next pot code in my database seems to be 5-68. That's why you see so many people claiming to have a 1966 Fuzz Face and so few who think they own a 1967 one
The pot with the broken shaft can possibly be repaired using parts of modern Omeg pots. Stu Castledine would know. Replicas of the original knobs are available.
Scoring a vintage Bulgin switch would not be so easy - and they're not the most reliable parts. There's a reason why many Fuzz Faces have replacement switches.
The OC83 sure looks like a replacement. If you're going to restore it, wait until you find a builder who has a stash of period correct NKT275s (i.e. not only Newmarket made, but also with the correct print) to choose from so he can find one that sounds good in your pedal.
Everything is transitional.
