Based on this product's specifications, here are some alternatives and similar models
Power Supply Unit Synology PSU 150W-RP MODULE_2 150W
Summary description:
The Synology PSU 150W-RP MODULE_2 is a reliable power supply unit designed for servers, providing a total power of 150W. It is compatible with the RS1619xs+ model and features a sleek silver design. With dimensions of 257 mm in width, 81 mm in depth, and 40 mm in height, this power supply unit ensures efficient performance and stability for your server needs.