If there are no marks/letters further forward then all we can say is that the tubes were by
Delcour-Dupont, with (good quality) steel from Cockerill.
It is unlikely that Delcour-Dupont was a primary gun maker
https://www.littlegun.be/arme%20belg...upont%20gb.htm
Post-1924 "CHOKE" only indicates muzzle constriction > 2 mm or about .008"
It appears to be a sideplated boxlock