Motor Drive pinion (Inside the gearbox)

[impmad2000]

I have been given a spare C5 Motor, and bought a gear box seperately. But I am still one part short of a useable spare motor !! The motor output shaft is bare, so no drive into the gear box. The bit I'm missing is this drive pinion gear, the one that mounts directly onto the motor output spindle.
Does anyone have a spare ? This is the brown gearbox, if that makes any difference.
Many thanks in advance.
Tim (Leicester)