Thank you for posting your inquiry.

It is difficult to be certain based only on a couple of photographs, but I am doubtful about the authenticity of this one. A couple of issues, as follows.

The marking on the movement does not look right. Checking the other triple calendar moonphase chronographs in my files, we are accustomed to seeing "Ed. Heuer & Co.", Switzerland, the Heuer shield, and a serial number, all marked on the movement. So when we see only the shield, these are usually not correct.

It is difficult to make a call on the dial. A lot of the details look good; the shield looks OK (but it is difficult to make the call from this one photo); but the main time of day hands seem to be too long.

All in all, I doubt that this one is an authentic Heuer.

Jeff