Based on this product's specifications, here are some alternatives and similar models
Power supply Dell M821J 525W APFC UPC – server PSU 525W, APFC
Summary description:
Dell M821J is a 525W power supply unit with APFC and UPC designed for server use. It delivers stable 525 watts of power for compatible Dell systems, supports active power factor correction for improved efficiency and cleaner power delivery, and is intended for data center or enterprise environments where reliable, continuous power is required.