I believe the brand is Grand Sport, and De Luxe would be the grade, but it could also be the whole name that is a brand name, the weird part is that there is also a french bicycle called the Gitane Grand Sport De Luxe. It's likely a re-branded pipe from one of the major St-Claude makers, and it was most certainly made after the war rather than during the war since the lack of good briar caused most of the french pipe makers to close up shop from 1940-1945(notable exception being, Courrieu Cogolin, who operated from southern France and therefor had access to local briar. The war also gave birth to the leather-clad pipe as a way to hide horrendously flawed pieces of briar.).