Based on this product's specifications, here are some alternatives and similar models
Rack rail Rittal 4946.000 — steel, silver, depth 955 mm, pack of 6
Summary description:
Rittal 4946.000 rack rail set: steel mounting rails in silver finish with a depth of 955 mm. Designed for installation in equipment racks to support servers, network hardware and other mounted components. Sold as a pack of 6 pieces, suitable for commercial server cabinets and enclosures where sturdy, standardized rack mounting is required.