WTB Danger Zone part

I'm still looking for the vertical shaft encoder (part 50-11575-01)
for a
Danger Zone. It's missing. Everything else works! This shaft encoder

looks to be a gear attached to a potentiometer of some sort - +5 and
GND in and *two* lines out. Why there are two is puzzling to me. Can
anyone tell me exactly what this encoder is, or maybe tell me where I
can get a replacement?

.