In perusing the Francisque Darne catalogs (these are NOT Darne catalogs, but, a different company) I encountered a version of the lowest grade sliding breech gun, from about the same period, mid to late 1930s that was available in 10 gauge. I have been aware of this for perhaps two decades, and kept my eyes open on websites here, and in Europe, but, have never seen one advertised. I’m not in a hurry to own a 6lb 10 gauge, but, would love to see evidence that they exist.

Best,
Ted