Donkey Kong Jr joysticks

[Scoots]

my friend's dkjr cocktail machine is missing this part of the joystick assembly:

http://imghost.eatshirt.com/scoots/stick.jpg

i could fabricate the missing piece, but i'd really like a nice measured drawing to go by if someone could supply one? or if you have a couple spares laying around for cheap i might be into just buying them outright.

any help greatly appreciated!