Great question, it's slightly smaller than usual headset and I believe its 22mm.
For now, I'll wait a week or two for any interest close by. If no further interest, I'll consider shipping.
That's what I thought, so is it a compatible stem or did you modified it to make it compatible?
I'm having a project of a vintage French bike and I'm curious.
What is the headset diameter?
Are you willing to ship this beauty?