Source for Panasonic WJ-AVE fader caps. The part ya touch 'n' slide

I’m missing one of these fader caps. I believe that they are the same ones as used on the AVE-5, yet are the smaller of the two sizes; as seen below, for SOURCE, AUX, and MIC.

Any leads on sources, good people? Thanks, Danke, Merci, et Gracias.