Body Plugs

There are two reasons Im asking. One is because there is rust damage at the back of the rear seat area, not the floor pan. there is another section under the floor that ties to the rear frame rails that has body plugs. I havent seen anyone making a replacement so I have to make one which would delete the plug holes. The other reason is mice chewing a hole in one of the plastic plugs and turning the car into a habitrail.