Trunk floor section needed 72 Duster

I am in need of a small section of the trunk floor, specifically the external section of the spare tire wheel well area between the fuel tank strap bracket area. The area between mine has rusted in the very center so I need to cut it out and replace it with new metal. If any one has a parts car that has this section it would be much appreciated because it would make no sense to cut the entire pan out and replace with the minimal amount of rust that I have. Thanks.