The master window switch is well known for failing at some point due to its cheap plastic and faulty design.
Finding a new switch from Toyota is nearly impossible, and even when one exists it is very expensive.
A used switch can often be found on eBay or elsewhere, but because these switches have also seen use and are over 25 years old, they will likely fail soon.
The best option (in my opinion) is to build your own switch.
Master Switch Diagram
Here is a diagram that I made using the BGB and a multimeter on my own master switch: