Ah. I do have my brake lever rigged to do that, but it's with a magnet and a reed switch on the outside of it.
What's funny is that I have that on the outside of the entirely-plastic ScootNGo brake handle, which has a normally-closed switch in it (meaning if I engage the brake, the switch is *closed*) so it turns on the brake lights when I squeeze it. It's pretty crappy, but I havent' gotten round to putting reed switches on the outside of my locking brake lever, arranged so that the magnet holds one closed and the other is open in either position, using one for the throttle cutoff and one for the brake light.
I wanted to use the nice brake handles off the Honda scooter that I've already got the left one of on the bars, but the stupid switches in them are worn out and corroded inside, and not easily replaced with anything else due to their custom design. Thinking about using some hall sensors out of computer case fans, since they're switching and not linear.
I dont' suppose the ones you have in a box are magnetic rather than cheap switches? If they are magnetic, maybe I could make a deal with you for them, if it's cheap enough (I mean, *really* cheap, unless you could wait a month or two at least).