These early Heuers (1940s-50s) are so much harder to research as almost all the information out there seems to be on the later models like Carrera, Autavia, and Monaco from the 1960s-70s. I googled as well and can't really find anything similar, most of the Heuer triple-calendar moonphase chronos seem to have a sub-dial at 6 o'clock. The Heuer logo looks very broad-sided to me, but I think it did vary a lot in the early days so who knows if it's wrong or not. This Breitling looks quite similar in layout, but it was described as a redial. Have you tried asking on "OnTheDash" ?