I've had many 55.2-59 panels with similar seats. Although the backs were metal. Sometimes known as Bomber seats. Fold then tilt forward after that. For Access to passenger side.
To confirm, spend time on the internet and you will be able to confirm if they are. Can't imagine what else they would be. Maybe some old coupes had those, don't know.

Last edited by bartamos; 04/21/2021 10:10 PM. Reason: More to the point of question
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