"Perfect" & "Original" are pretty strong words to use in any advertising and you'd want to be 110% confident to back it up. There's 6 things I can see in the photos that aren't quite perfect or original...
1. Near new rego plate. Has it been relicensed after a restoration??
2. Body seal - Tailgate area. That gap is a bit wide for a "perfect" description.
3. Spare Tyre Cover. Water stains on both L & R edges??
4. Rocker Cover. That ain't original!
5. Air Cleaner. That ain't perfect!
6. Wheel Trims. Or lack thereof...
I may be wrong, but isn't that a '77 grille? I'm a bit dubious about '76 120Y's having clear side markers from the factory (for the Aussie market) as well and there's no mention of a complete, documented service history either. You'd think that a car of this so-called calibre would have one AND it would be shouted from the tree-tops.

Don't get me wrong, it is a nice looking 120. But at that price??? At the end of the day, if the seller actually gets someone to look at it in the flesh, the "prospective buyer" would either have too much money (which will only benefit anyone that has a good example of any earlier Datsun) or are just there to tear shreds from, and laugh at, the seller.

Just sayin'...