Ralph, I'm pretty sure those were blocks made by Henry and shipped to France for the war effort. They were discovered in a french warehouse several years ago as leftover war surplus. Seems to me there were maybe 200 of them. Here's a blurb from the HAMB......
"The actual owner of the French Flatheads is Brent Mullins (http://www.mullinsjeepparts.com/). He restores military vehicles and goes all over the world buying military surplus. He bought the French Flatheads and imported them to the U.S. He sold them to Halibrand and got them back after they went bankrupt."