Any good hardware store has them in the nuts/bolts section.
 Sean G

      From: Edward V Barger <edvbarger@MAC.COM>
 To: vanagon@GERRY.VANAGON.COM 
 Sent: Tuesday, April 4, 2017 2:28 PM
 Subject: Plastic part for the louvered rear vents
   
HI 

Just came from the VW dealer went to get the small square blocks used to secure the two rear louvered vents 

They press fit into the metal and accept the screws the retain the louvered vents 

parts man says the are no longer available from VW  

any one know of another source 

Edward V Barger
edvbarger@mac.com
310 922 6251