Based on this product's specifications, here are some alternatives and similar models
AC Adapter 2-Power AP.06501.013
Summary description:
The 2-Power AP.06501.013 compatible AC adapter provides a reliable output voltage of 18V. With dimensions of 49mm width, 118mm depth, and 32mm height, it is compact and easy to use. The package dimensions are 128mm width, 190mm depth, and 54mm height, making it convenient for storage and transport. Ideal for powering devices requiring 18V, this adapter ensures stable performance and safety.