I've got 2 pairs of 911 / 914-6 metal air filter bases, these have the raised lip and locate the inner panel of the metal 911 air filter . Does not match the plastic 3 hole plastic top boxes. . Fresh powder paint with rubber sealing gasket.
1 set has clips, one set does not - only the bases.

Set with clips $160 shipped USA sold on Ebay
Set without clips$140 shipped USA sold on Ebay