Agree. Nice find. Also agree on the stem. Hard to tell but that looks like an early one, with the exposed nut on the back of the clamp bolt.
Look on the underside of the stem and there should-might be a number. Those did come in the French size of 22 mm, my Champion Team came with one,
but on my TdF a standard 22.2 fit through the headset top nut and into the steerer just fine, for some reason.
That stem, if French sized, and in good condition, may be worth what you paid for the whole bike.