Not sure why they are telling you these are NLA...below is the link for the 80mm M14 bolts. I just replaced these on my 1976 car which had M14x1.5x75mm bolts that were Grade 10.9. These replacements were Grade 8.8.
Given it's still a Porsche part number, I'm sure grade 8.8 is fine.
I went with the 5mm longer bolts as I was using a distorted thread 14mm thick lock nut. The OEM lock nut is sort of thin, so the extra length isn't needed I guess.
900-082-092-02-OEM - M14x1.5x80mm Bolts