Boeing 787-9: Seating 250 – 290
Range 8000-8500 nm
Cruising speed 0.85 Mach
The distance between Auckland and McMurdo Station is 2473nm: 4.4 hours flying time. Available flying time at cruising speed is a whopping 15.1 hours, so that would give 6 hours for sightseeing. It would be a long day, but I'd pay around NZD900. And given the history, it would be one of the safest scenic flights available.