[Hillyard]

I stumbled upon this on theFrush's car but he has no idea where the previous owner got them. They appear to be a firewall plug but I dunno. I have checked some local autopart stores but haven't had any luck.

Thnaks
Hill

 

[Foci_Fosho]

that looks to be the same type of plug/grommet used in the door jamb.

Look for rubber grommets/plugs used for automotive.
ebay has 'em...