I found a reputable store in selling Mark XII without the word "MARK XII" above automatic on the dial. The seller refers to it as an early dial version. Is this authentic?

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I’m considering buying IWC Mark XII from private seller in chrono24. I’m just wondering if I should be worry about receiving a fake watch? Pictures look very legit.
I mean Mark XII is not a popular watch like Rolex Sub and I never heard of a fake one.