Jeff: Please find attached photos of my Siffert with decimal bezel. I acquired it a little over a year ago from a seller in Phoenix who claimed it was from an estate sale. I've had it serviced by Craig in Oregon and he told me he believes the bezel is original to the watch, though he didn't expound on how he arrived at that opinion. As you can see, it's in very nice condition and runs perfectly. And as you surmised, this is a later Siffert and it makes sense to believe the bezel is original to this watch and not a replacement.
Thanks again,
Bob Keller

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