For now, you can get a replacement motor with gear for around $50. Look on
http://car-parts.com/ FWIW, Ford want's about $160 for a new motor.
Also, I think the key to not having the gear strip is keeping the tracks lubed. I used 3-in-1 oil on the tracks (which where dry) and it opens and closes with ease. You can hear a difference in the load on the motor.
As for me making a replacement brass gear, that's on hold right now. On the back burner until further notice.
