NitroX
Hope this might be of some use.
I think it's "DUMOULIN".
I don't think Harold Wolfe makes any double rifles however he was knocking up a drilling in 577 NE 577 NE (2 3/4) over a 12 G.
I dont believe Winchester has built any double rifles since the Grand European OU guns which were finished by mid 1980's.
Baikal make a fugly OU rifle that I think is a 1ZH-94 or similar.
Another possible entry could be Ziegenhahn & Sohn as there was an advert in Hatari Times #13.
Also maybe Sarasqueta from Spain??
Zoli?