XJ Rear body panel ?

Hey fellas, brand new project XJ owner here, just bought a one that needs a little rust repair, mostly behind the rear bumper, haven't removed the bumper yet, but im online doing some research on rust repair, just curious what the panel just behind the rear bumper is called, and is the panel available, or do I have to make my own? thanks

 

Welcome @streetmaster56 ...XJs are awesome jeeps. Post some pics now and during the build. Lots of aftermarket parts are available for the XJ.
Start by looking at some of these sites as other XJ owners can provide their favorite sites

https://www.crownautomotive.net/Jeep-Cherokee-XJ-Body-Parts.html
https://www.4wd.com/b/replacement-p...t-body-parts/xj-cherokee-body-parts/_/N-clb1u

 

Rear quater panel, and they are known for rusting, but replacements are available.
Quarter Panel from Summit Racing
Panel from rear door to rear of vehicle, all below rear window from Quadratec
Not sure what kind of build you are wanting but you might look at doing a "cut and fold" if there is enough metal there to salvage.