While looking for stock for the iPhone 8 $59/month deal at Harvey-Norman, I found that the 6S Plus 32 GB is on clearance for $747. There is some stock for online ordering as well. JB Hifi has a similar in-store price of $749 (jb hifi online shows a different price of $849).
If you have two registered Amex cards with the HN $100 credit, then add a $53 filler, and split the $800+ payment over two cards for a fantastic deal on the iPhone.
That sounds very high for a over 2 year old phone…