71 a/c-control plastic slider issue!!!

[FIREBALL]

Hey Guy's I have a slight issue and need to know if there's anywhere I can get a couple of plastic sliders for my knobs on my temperature control. I'm talking about the black plastic sliders that slide inside the control unit (there right behind the chrome knobs u push and are square shaped) if anyone knows where I can get some or has took a few units apart and parting out some arms that are good I'm interested in mainly the middle arm mine disintegrated into pieces, Thanks in advance Kurt