Possibly just an illusion but the NDS looks like it has smoother contours to me. I'd ask the seller purely for peace of mind... I've not owned a pair so I'm by no means an expert!
I asked the question. Buying from an older track racer in Glasgow. Says he has had them from new - so the original set. Must have been optical illusion. Not to find an ISO BB and chainring to go with them.
Is there anything that suggests they aren't? Guy advertised them as a pair with same length 172.5