Additional info/pics needed:
Pics of the joint faces, pilot, and pin.
Check for a weight bolt. It will likely be deep, you'll need a flashlight. If you can get a picture that would be great but difficult.
If the weight bolt is slotted it isn't a JOSS. I don't think it is a JOSS at this point, but if it is you want to find a hex keyed bolt. As far as I know none of the modern JOSS have slotted bolts.
If it is slotted it supports the idea of Viking, but it could still be another maker. In addition, Viking also uses hex bolts.
What I am getting at is that if it is slotted, it isn't a JOSS, at least not from that era.
JOSS weight bolt:
Viking can look the same, or be slotted.
Edit: Since weight bolts can be changed, none of this is absolute of course.
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