Jennings Governor

[shortrackskater]

One of the recent 4 machines I bought is a Jennings Governor. I'm having a difficult finding out any information on these. A lot of photos on the internet show a Sun Chief, calling it a Governor. And I've I've also seen "Sun Chief Governor." My understanding was the Sun Chief had the manual-fill jackpot. My machine has the more complicated auto-filling jackpot. There's no keyhole on top of the Indian head.
After a LOT of de-gunking and work on the sides and the jackpot mechanism, it seems to be functioning. I'd like to replace it someday but not quite sure the approach, and cost of replacing aluminum.
I found two serial numbers: The case is 202208 and the mechanism is 201349. Is there any way to figure out the approximate age of this machine?

[sam2002]

Jennings governor 50’s-60’s era machine. Lots of great info in these books, if you can find them they’re worth the money.

[shortrackskater]

Yes the books are great thank you.

However I'm still trying to figure out the year of this by the serial numbers if possible. I thought somewhere, there might be a list showing s/n and dates.