Based on this product's specifications, here are some alternatives and similar models
Backplate Watercool 16070 — aluminium computer cooling system part, black, 1 pc
Summary description:
Watercool 16070 backplate for computer cooling systems, made of aluminium with a black finish. Supplied as a single piece, it serves as a mounting and reinforcement component for water blocks or cooling assemblies, improving stability and even pressure distribution on motherboard or GPU mounts. Suitable for custom liquid-cooling builds and component upgrades.