Gil,
Ive only seen a few rifled barrels on French guns. I never saw pumpkin ball type slugs in France, notable to me because every gun proofed in France with a modified or tighter choke has a warning dutifully stamped on the flats, warning against their use.
Foster type slugs were all I saw, Brenneke, Winchester, Federal and Rotweil were the brands I saw. French proof, high as it is, allowed for use of American standard ammunition.
Every gun shop had a nice selection of slugs, the French had plenty of pigs that needed to be killed, but, they were short on most everything else except, maybe, ducks. They were really short on places to hunt. The damage to a crummy little French car after it hit a 500 lb wild pig was immense, and people often got hurt. Every shop also had a few Remington 870 Express models, usually with a slug barrel, or two barrels, and red dot sight systems or low powered scopes for same. 12 and 20 gauge, just like here. The guys who hunted pigs were welcome everywhere, the pigs seemed like a hell of a nuisance.
I would guess that the 870 was the most popular gun in the mid 1990s in France. None of the gunmakers was happy about it, but, it was reality. None of the gunmakers I met were regulars at bird hunting, sometimes going years between treasured invites from friends or acquaintances who had the means. Woodcock seemed to be what everybody wanted to hunt. But, few people needed a Raye barrel to just dream about woodcock they were never going to see, much less hunt.

Best,
Ted