wheel well area on 72 burb

[xman]

I apologize up front for this and if it gets deleted I understand but I am looking for this spot at the right rear wheel opeing behind the quarter panel as the previous owner did such a wonderful job at repairing this area with a chunk of ABS plastic as a patch. My fab skills are nowhere near like most of you can do. If anyone can help it would be appreciated. I have checked the parts section and of all the burbs being parted out they are all shot due to rust