I found this cheapest one ($927 + Shipping) and there are other sellers below.
$959 + Shipping @mwave (in stock)
https://www.mwave.com.au/product/synology-diskstation-ds920-…
$959 + Shipping @cplonline (pre-order)
https://cplonline.com.au/nas/synology/synology-ds920-disksta…
$1093 + Shipping @centrecom (pre-order)
https://www.centrecom.com.au/synology-diskstation-ds920-4-ba…
bought 918+ 6 months back. i will wait for couple of years, this way ds920 will also go for time test :)