Weird microphone needed

[SnakeOiler]

For a 1970's Sears am fm PA cb car stereo. It has 7 pins in a semi circle, but no pin in the middle. Is this proprietary? I cant find one anywhere so I am posting here. Thanks in advance for help and replies.

[source]

I think i might have something give morre info .or show picture

[SnakeOiler]

I am having difficulty uploading a jpeg from my phone, maybe too big of a file?

[source]

Will check on it