GMT 6542 Bakelite bezel and insert id help.

[James 45]

Hello I have a very old bezel I am not sure about.
I got it from a rolex dealer deal where i got a lot of parts from the 60s-70s
and boxes etc.

Well this bezel was in it, among others.

I just don't know what year it falls in? I know 1956-59 but which one?

And of course if there was something wrong with it(fake anything)
i would like to know that to.

Measures 38.25 od and 33.25 id of the bezel
30.04 id of the insert.
I wont take the insert out incase it breaks so i have to od of the insert.

Thank you for your help.