Cheapest I can find at the moment including delivery. This three pack comes with the Lighting Node CORE. Use coupon code PRESS20.
It isn't as cheap as this deal a few days ago https://www.ozbargain.com.au/node/583291. I wish I got it at that price but these fans hardly go on sale as long as I've been hunting for them.
I've recently bought one of these for my new computer build and these are great fans. Needed another 3 pack to go into my Lian Li PC-O11 Dynamic White case :D