Sorry, but the grey sub dials look uncommon and not Heuer-like to me. Also the red sub-dial hands look like they were repainted, for the hands holes should not be filled with colour.

Some remarks: Referring to the OTD files, the 'Chronomatic' should have been the first Automatic Autavia (Cal 11). The printing of their sub-dials continues the Heuer-usual style, also seen on the handwound Carreras or Autavias. And it’s the same for the Cal 12 equipped Autavias. So if this Sunburst Autavia is equipped with Cal. 11, I would allocate it built about 1969 to 1971.
Why should Heuer change the sub-dial design, they have used for such a long time? Just to come back to the former style? Maybe it was an experimental dial?
The Monaco dial discussion brought as one of the results, that the number 4 should be printed in a special manner. Looking at the Sunburst the 4 is closed indeed, but this looks like a pointed top, not a flattened one like the usual Heuer style.
Unfortunately the auction photo doesn’t allow to figure out, whether the proper detail in the script ‘Heuer’ and ‘Autavia’ is given.

Charles, maybe I'm a newbie, in comparism with you and your experience as a collector and seller of fine timepieces, and might be, my first post was a bit striking in your eyes.
But imo, this forum is a place to ask, discuss and learn, even for the inexperienced. So please share your knowledge and tell us all you know about this Sunburst Autavia, especially about these grey sub dials with their red hands. Maybe you can add a more detailled photo?

Anyone else who can share? Jeff?

Thanks

Martin