I finally got the specification sheet from Brush industries:
no price yet, likely dependent on volume.
So.... I guess I need to test an amplification circuit with my current coil heads and get a resistance reading to see if this would be compatible. If anyone has any advice on this please holler at me.
I recently learned about baluns and wonder if this might help in some way or be a way to completely side step this kind of specialized sensor by building a general purpose antenna.