For some reason, Expedia's New Zealand website is offering even cheaper deals than out of JFK. They're not direct, either having stopover in Ghana or JFK, but now that the JFK-Joberg deal's dates are slowly vanishing at the low rate reported on yesterday's post , other options have been found, as reported on Dan's Deals.
Here's the info from that website:
From DC the fare starts at NZD 544 which is USD $391. From Boston the fare starts at NZD 651 which is USD $468.
As with the NYC deal, cheap fares can be found for departures from August through December
You can find cheap dates using Google Flights and then plug them into the link below to save approximately $390 off those fares.
Sample $391 dates from Washington DC-Johannesburg:
-October 30-November 9
-November 27-December 7