Exhuast rattle help

[grandkodiak]

My exhuast is kinda slaking down, I guess the hangers just cant take the weight of the borla for so many years, and its drooped down about an inch or so, just enough so that the pipe right behind where the exhuast splits to the stright back and muffler split, it rests on top of some piece of metal that runs from one rear tire to the next. sorry i know almost nothing about suspention parts so i dont know its name... and when the car is cold the exhuast rattles something nasty against it. it goes away when it heats up but i'm afraid its going to wear a hole or dent the system. i'm gunna take it to a shop in the next few weeks to get all new hangers and really have it set up well. but what i want to know is what can i put between the exhuast pipe and the metal piece to dampen or at least press between the pieces? i was thinking rubber or plastic since its easy, but i'm afraid it will melt or burn... same with wood. any ideas guys?

[grandkodiak]

PS where can I get the equip I need to replace stock system ie. hangers?