WHERE CAN I GET POWER WINDOW PARTS?

It's kinda hard to see doubt if I can get a pic. There's a bracket that runs along the bottom of the window and there's one roller towards the front and one at the back of the window. The front one is loose. I don't see a way to tighten it maybe I could try to pinch it tight with some plyers or somethin.
Thanks for the response.
 
I don't think it'll be a problem changing it. Just don't really wanna buy a whole new regulator when it's just a small part that needs fixin. Looks like i might be able to take it apart and fix it with a rivet gun if I have too.