The doors for the Suburban are only made by 1 manufacturer Tri-Plus so no matter who you buy from they'll all be made by Tri-Plus. We carry the complete Suburban lower rear quarters plus every other patch panel made for them on our patch panel page located here
https://gmcpauls.com/Patch_Panels.htm
The Suburban rear sill is not reproduced so you'll need to repair yours, find used or have 1 fabricated by a good metal shop.
Paul Jr @ GMCPauls