Based on this product's specifications, here are some alternatives and similar models
Playground pole discs Maxwel set, diameter 15 cm, 10 pieces
Summary description:
Set of 10 Maxwel playground pole discs, each disc with a diameter of 15 cm. Designed as replacement or accessory parts for children’s play structures, obstacle courses and training poles. Lightweight, stackable discs suitable for marking positions on poles, creating climbing challenges or guiding drills in schools and playgrounds.