The fastback is the coupe. The other 2-door 120Y is a 2-door sedan, I've still got one sitting around but it's only good for scrap now.
That one in mittagong sounds good, although plenty of people will advertise that they "only have 80,000km" because that's what the odometer says. Most 120Y odometers only go up to 99,999 before they click back over to zero.
Good luck finding one, I'd love another but for some reason people suddenly thing they are worth a fortune...