Yes, those are cantilever posts. Yes, that's a 1" steerer on a crowned fork. Yes, that's a level top tube. And, yes- those are down tube shifter bosses. This is not the new formula- it is the classic.
I found a source that has continued the manufacture of the Pacenti line of fork crowns. I was worried that they were extinct but now there seems to be an endless supply- not something you can say about many frame building materials in the 21st century.
The frame will be going to a place where it rains a bit so there's provisions for fenders. There's also room for some pretty big tires, at least by CX standards. The only newer feature on this frame would be the third set of bottle mounts under the down tube that are so popular now.