I think I have a pair of white sun visors from a '71 Suburban,along with some other interior parts like the ashtray,glove box door,defroster louvers,and a couple of dash clusters,other misc stuff..have to dig thru my rubble and see if I still have the stuff,pretty sure I do..I have some from a '73 K-10 too,but they are different..
I've tightened up loose visors by putting a layer of duct tape on the shaft after taking them off,then tightening the pinch screw tighter..one truck I had that failed to work,so I glued a hunk of velcro to the back of the vison and to the roof ,that ended that problem!..