Does anyone make replacement plugs for these? These might still be salvageable but I'd rather just go ahead and put some new coated ones in if there are available. Talking about the rusted circle plug below, and I think there are some oval shaped deals with arms too. That slit just taps out and then the plug comes out from the inside right?

 

Check ebay maybe? Honestly if you're really worried about them I'd pull them, sandblast, and paint.

They don't just pull right out though. They've got some serious adhesive holding them to the floor pan.