Those are Lyotard mod. 23 pedals, designed way back in the 1930s by French track champion Marcel Berthet. They were in production for over half a century (mid-30s to late 80s), but alas, Lyotard is no more. They turn up on eBay fairly often, but tend to be pricey. You also have to be careful because they were available in 3 different threadings: 9/16" x 20tpi, 14mm x 1.25mm, and 1/2" x 20tpi.

The Sakae-Ringyo SP-11 appears to have been inspired by the mod. 23, as is the White Industries Urban Pedal.