Jonathan, nice set up! The French made Michelin X above are made from original molds with modern gum. I grew up in France and just about every French car was equipped with Michelin X which was the first radial tire. The radial tire was invented by Michelin in 1949. in 1951, the Michelin X was factory installed for the first time, by Lancia on the Aurelia. Starting in 1955 the X was installed on most cars sold in France. I can tell you the thread pattern above is the only design I have ever seen, mounted on Tractions, 2cvs, Renault 4cvs, Dauphines, Facel Vegas etc. I have never seen the thread on the English made Michelin X before, not in France. So these days, if you want a Michelin X that is the thread you will get. Incidentally, for myself I would never buy a NOS tire as the gum deteriorates with age and would make the car rather unsafe. (for museum purpose only).
In the 50s, the X was so superior to any other period tire that it was installed on many rally cars of the time and without factory support with victories in the Monte Carlo, Mille Miles, Acropolis, Tour de Corse, Etc.
Emmanuel