I know something that seems to be impossible to find.
Miklos the guy in Europe that restores E9's ( like 10 or more in his shop) is looking for brake caliper bolts. The one's that hold the calipers together. Sorry I don't have the part number in front of me. Just found the part numbers he posted. This is rear brake pads bolts, M7x71x1 and M7x62x1 factory numbers 34211108775 and 34211108775
They are the M7 hex head grade 10 or more bolts. One is 71 mm and the other is 62mm according to Miklos.
FYI- I called PMB that does the Porsche caliper rebuilds and they don't have any or a source. I called Belmetric same.
Someone in Europe posted this site
DIN 912 Zylinderschraube M7x70 - 12.9 brüniert ✓ Online Bestell Shop ✓ schnelle Lieferung ✓ großes Lager
www.tola-tools.de
But they don't have any stock.
You'll be a hero Harry if you can find these and the nuts.