Interesting set, but it looks like it is missing the PG7, but has what looks to be a late model Pentel 11 (which could be a 0.7mm) in its place. Of course it could be from before the PG7 was released.
The description says the PG5 is from the 80’s, but the rest is original to the set.
I have one of those cases. But it’s empty.