That piece is longer than the black rubber because it combines the width of the heel shifter and the rubber spacer in one.
The rubber is beneficial to have there because it keeps the shifter snugged up against the primary which keeps it from vibrating. Is there anything in this piece to keep the pieces under some load? I would be afraid of vibration in the shaft wearing away the aluminum in the shifter hole of the primary.
Chief, are you sure that's rubber? It looked like a wrinkle black finished, metal spacer, last I checked. I don't have my bike to check it again now. But if the Kury piece is one piece, and replaces the rear shifter arm and the spacer, that would work. But is there just a crome replacement for the spacer alone? I'm not sure if I'm removing the rear shifter arm yet. Hoist!