Hello, if you don’t have any luck here. You might also post what brand of radio and model the knob is for. There are (2) Facebook Radio knobs and parts groups. They are private, so you would have to join. I haven’t had much luck in posting links here in the past. So you could pm me.
https://www.facebook.com/groups/630903414390607
https://www.facebook.com/groups/529145247690609/#_=_
Hope this helps.
Tony