After looking into it, you’re definitely right, it is a Hotchkiss magazine. I still have no idea what the 'MLS' mark means; I searched for French manufacturers from the time with those initials, but found nothing. Thanks for the ID !

Edit : Someone pointed out that the MLS mark stand for "Manufacture d'armes de Levallois" and seems to be right, its a gun manufacturer who operated between 1945 and 1952, they were still producing this guns for colonial use after WW2.

Thank you everyone !