This is a knock-off of the Gi-Go 3-16-B1 mold. It is marked MADE IN CHINA on a front hoof and no markings on the back hooves.
These ones may be from Dollar General. They are marked CE and MADE IN CHINA on front two hooves. They have a heart and dots in their eyes.
These ones have no symbols, except for red who has a Dollar General code printed on her side: