Convertible rear arm rest panels. (I think it is a side panel and extra vinyl to recover the hinge cover) OPG has them listed. https://www.opgi.com/interior-acces...rear-4pc-vinyl-pui-cra30p.html?size=&color=LB
It's a piston cover. It may be easier to get it recovered than to find a new one. At least it was like that in my case.
I plan on respraying mine with SEM 15103 Super white. You You can top coat it with a pearl spray from AMES if your interior is pearl. It looks like you have a pearl white 70 deluxe interior. Someone can correct this if wrong, but I believe the interiors in ‘72 were just white with no pearl? https://www.v8buick.com/index.php?threads/pearl-white-interior-spray-paint-1971-gs.366519/
They make the metal cover and precut the vinyl in about 8 colors, but I have never seen the completed piece sold. 64-67 https://www.opgi.com/sheet-metal-bo...dy-convertible-power-top-pair-km02050-pr.html 68-72 https://www.opgi.com/sheet-metal-bo...panel-68-72-a-body-upper-pair-g241317-pr.html
You have to pull the back seat. It will be apparent once the seat is out. Two screws on front side and one usually screwed to the back. Plus two on the lower arm rest front piece. Those two sections are connected and will come out as one unit.
