Wouldn't drilling a round hole in the case and using a push button momentary switch be better as a "brake" application than a weird spring slide switch?
I agree. I would prefer the spring-loaded mini toggle, but the idea is the same. You probably would not even have to drill
unless you chose a large toggle or pushbutton. It would probably fit through the rectangular hole and secure with a washer and nut.
With a little handywork, you could cut out a small metal or even styrene sheet painted black to completely cover the rectangular hole and make it look good, as well as be functional.