What do you call the area below the engine louvres that the hinges of the rear deck bolt to? As can be seen in the photo I have a bit of rust.

I might be able to patch in some sections, but am wondering if I can buy a new one (have searched but to no avail partly because I don't know what it is called).

Does anyone have a donor one willing to sell?

viiking

To my knowledge that panel is not available new. I'd have a look on some of the English websites as they have more rust and consequently more rust repair panels available.

common place for rust, to replace that piece would be a mojor pain it the ass whether your going the spotweld removal route, or just a cut and butt weld job.
i just took out my parcel tray and i can see that gutter is spotwelded up into the body real good...
i have heard of someone on this site remove the vent section inside the engine bay to paint inside there,
then epoxied it back in, not sure which route he went with getting that out, but that would be the first step,
unless you are going to cut and splice in a replacement,
which i would suggest not doing because it will rust up along the weld on the rear where you wont be able to get to, to grind or even to paint fully, and bugger grinding down a weld on the front side in the gutter too.. lol
Iv never seen a replacement section online either.
Goodluck