This was just listed a few hours ago by Bing Lee, great price for the new Sony KD75X8500D. Bing Lee recently dropped their price from $5999 to $4899, combine that with the 20% off eBay coupon CUT20 to make it $3919.20.
Cheapest elsewhere is $4928 at The Good Guys, Harvey Norman & JB Hi-Fi (until 25/9). See staticeICE. One previous deal for it here for $5449 back in July. The Bing Lee listing price of $4899 is actually the cheapest already before the code.
Sony model info:
X8500D KD75X8500D 75 inch 4K HDR TV, available early May 2016 — RRP $7,499
Some reviews here
Unfortunately it's NSW only, click & collect for free or $40 postage for most of NSW (your address must be set to NSW).
Would totally buy this TV if I was in NSW. Currently looking for a 70 inch TV within the $4k range. :(