As Larry asked, I'd be curious to know if there is a VIN tag on the left side of the dash at the base of the windshield. There should also be one riveted to the driver's side door jamb. If NOT, I would run far away. I might even report it to the police/CHP.
https://www.shouselaw.com/ca/b...remove-a-vin-number/
The cover plate without the engine number stamped on it is most certainly a reproduction like this one from Hall:
http://hallpantera.com/cgi-bin...a-inc&item=21498
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