Craig - the bezel is not correct as far as tradition goes however we know that there were bezels options (MH and Tachy) and in some cases customers prefered to choose a "non Standard" option. This looks like a correct 1163 decompression bezel and therefore contemporary to the model. It also has the patina of a bezel that has been on a watch for some time so it may well have been specified by the original owner. Its a different look, somewhat less functional than the traditional bezels but certainly worth keeping if you decide to change it for the tachy bezel.
Great find though.
regards
Paul
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