Ok, here's the latest. The parts department at the dealer said the rusted bracket is available and only $4.50!
BUT...Being the cat is stainless it has to be tig welded and neither the dealer or the repair shop I use will not weld it on without removing the cat.
I'm torn, They assure me there is another protective shield and there is nothing vital, mostly just added protection for the trunk.
Neither would commit to a estimate but both said it would be costly.