What parts do I need?

[Claus]

When I put my Tamiya 3 speed transmission together with aftermarket parts I noticed there was an extra hole in the front of the case. At first I didn't know what that was for but I now see there is a second shaft to keep the shif fork shaft from spinning and binding up the linkage. What parts do I need to buy, example Aeromax shaft bag A, Etc. Even if it's not necessary now that I see it I want it.