I was never able to find any.
what I used was a small piece of rubber type stuff I got from a glass repair shop. it goes between glass sheets when shipping on trucks. it is different sizes and easy to trim down and a dab of glue they stay put and stop the rattle.
until like my stepside it just gets so much rust their is no hope for a rattle free truck LOL!
might even try some of the stick on stuff that goes on table top furniture stop scratches. felt one side sticky tape other.
I check the old 82 bed out back and see if they are their and I can get them off in tact for you.
Okay thanks buddy. I've got some rubber wedged in there now so I don't go crazy when I have rear slider open