Here is how you reproduce the not yet reproduced 69-70 parking brake switch.
Make the ABS body and the end by 3D printing.
Make a bending jig to bend the beryllium copper contact to right shape and bend the contact strips.
Heat treat the contact.
Assemble and secure the parts.
You are done.
Changed the original design a little bit so the contact does not break due to fatigue like the originals did.
Cycled the black switch 2500 times on the 70 Cougar pedal I have off the car; it did not brake and did not stop working so installed it on my 69 Grande.
Left to right on the pictures below are; broken original switch, 3D printed ABS parts, contact, final product.