I would very much like to find this vintage movie

Belles-soeurs (1977)

Also Known As

Ces salopes de belles-soeurs

Les Belles-soeurs

Les Salopes

Une Belle soeur

https://www.iafd.com/title.rme/id=56bb4336-1774-4850-8ee8-c75234ebf8fa

https://www.egafd.com/films/details.php/id/b01152

Thanks,