These are welded to the body rail, which is what's actually rusted. What I did with mine was to weld a patch to the rail, completely bridging the hole, then I welded the original mount back after cleaning it up. More bad news... The fuel tank is immediately behind this location, so unless you are totally insane, it will need to be drained and removed before you light off that torch. Also remove all the carpeting and liner material from the trunk, and keep a hose or extinguisher handy.

You may be able to get the bracket from a dealer, but replacing the rail is impossible at any reasonable cost. Patching it the only course of action. And 124 parts won't work here.

The body rail is a critical member. The structure is probably redundant enough to tolerate a patch, you are on thin ice if it goes much further. I think the car is trying to say something ... Its past its prime, time to think about that.