I did some searching on a replacement for the mounting section of my fuse/relay box. Mine was mangled pretty bad in the crash. Just in case anyone needs one I was able to find the GM part number 25974391. It is a discontinued part but there is a GM parts warehouse (wholesalegmpartsonline) that bought up all of GM's discontinued stock. I ended up paying about $80 for it including shipping.
Keep in mind this one is only for the newer SS models but thought I would post it in case anyone ever needs one.