Help ID a vintage HP calculator part

[susanfy]

Hello. I hope this type of post is allowed. Please forgive me if it is not.

I have tried for a long time to identify this part, with no success. Many years ago, I sold my father's HP 97, so I thought it might have something to do with that as it seemed to be about the same age. But try as I might, I haven't been able to find another one like this in google search, Ebay listings, or in the HP museum.

Thanks for looking and sincere apologies if this post is inappropriate for this forum.