On closer inspection, I don't think these are NOS.
Look at the open box pictures of the fender. They don't seem to have the inner brace that bolts them to the apron and the cowl. I'm bumbed. They apear more like a skin than a fender.
to me they look NOS, ...not knowing which brace you talk about...is that brace a separate piece? as far as I know ,theres really no "fender skin", just fender....and if they have been in these boxes all that time, the box says "fender" on it....the 69 fenders I`ve seen off my buddys car looked like that...