Your J-wrap doesn't look that badly damaged. Photo's may be deceiving though. If you are insistent on replacing, then why not try a self-fix first. If it works, then you've saved yourself some money. If it doesn't work, then you've lost nothing to begin with.
Remove the panel, lay it on a flat surface, and with hammer, a few choice pieces of wood, pound away and refashion the J-wrap, removing the dents. JB weld for metal (or if you have the ability to weld aluminum), you can close up any ripped out holes or cracks. Careful work, and then finally spray paint can restore the damage to looking like new.
Personally, I'd try that first, before going through the expense of getting new material and the cost of shipping.
The second alternative is to just leave it the way it is and forget it. I dented up both of my rear corners (I still do not know what that actually happened). I broke out one side marker light too. I replaced the marker light and with just a bit of pushing and pounding, I was able to remove most of the dents, spray painted and resealed. Yes, the dents are still there, but they are not as noticeable. It's been 5 years since I did that.
Good luck, which ever avenue you choose.