Rare tinnie for authentication

Good morning!

I recently acquired over 40 tinnies, WHW tokens, and other various pins. I have most identified and authenticated but this one has me stumped. I chatted with a couple friends of mine who are experts and they are almost certain that this is authentic. The only thing holding them back from deeming this pin authentic is the hook for the pin. They said that there were several types of hooks but suggested I get other opinions before deeming this piece authentic. What say you?