Not sure what to call them.
They are the two plastic pieces that go around the mirror arm, and inbetween the bracket.
The ones that I was sold were plastic, and I went to torque the passenger side, to take some of the movement out, and and it snapped.
Do you possibly see a market for maybe some aluminum ones???
They would need a "U" shaped groove for the mirror arm, and a hole through the center for the bolt.
Just an idea. Something I wish I could've found a while ago.
Erik