Based on this product's specifications, here are some alternatives and similar models
Mounting plate Rittal 8617.600 for racks — galvanized steel, 900×400 mm, 2.5 mm
Summary description:
Rittal 8617.600 is a galvanized steel mounting plate for server and network racks. It provides a 900 × 400 mm flat mounting surface with 2.5 mm material thickness and a grey finish. Designed to be fixed inside rack enclosures, it supports mounting of equipment, cable routing and accessory installation in industrial and IT cabinets.