Tim,
I have a Pegasus Racing catalog that lists a hydraulic brake light switch with a 1/8 NPT male thread. The part number is #3601, the cost is $10.08 US. You can reach Pegasus at 1-800-688-6946, or on the web at
http://www.pegasusautoracing.com/
The switch has 2 pins for wiring connection and is normally open.
Good Luck!