Makers Mark Please help Identify! Made in Italy Fruit in Relief plates

these plates are hand painted fruit in relief- on the back is the mark, impressed into the clay: a triangle with letter P below the base, and letters N and S on the sides. At the bottom is : HAND-PAINTED_ITALY.
I know I have seen this mark or a similar one once before, but cannot place it. I have been looking for some time now and cannot locate a reference for this mark. I have used this site before and have had success on three occasions! Please, if you know the name behind the mark, please reply..
I do appreciate your time and thank you as well.
C-