Yes, it appears to be the pressure sensor from the pedal assembly. There's a photo of one in-situ here:
http://forums.arcade-museum.com/showthread.php?t=75550#Post1021472
It's not a user-replaceable part according to the manual:
"The only parts of the pedal assembly you can replace separately are the set screws on the hinge and the pedal tread. You must purchase the rest of the pedal as an assembly because special techniques are required to assemble it at the factory"