I've been price monitoring this for my new m-itx build and this is the lowest it's been:
https://au.camelcamelcamel.com/product/B07WC7683C
Cheaper than any local AU shops that I could find:
http://staticice.com.au/cgi-bin/search.cgi?q=sapphire+5700xt…
Mwave $749 - https://www.mwave.com.au/product/sapphire-radeon-pulse-rx-57…
PCCG $779 - https://www.pccasegear.com/products/47782/sapphire-radeon-rx…
Won't get into the technical stuff but this is arguably the king of mid-range cards. Performs better than its similar priced Nvidia competitors (2060s and 2070).
EDIT: Please note delivery estimate is 6-7 July, so that's roughly a month's wait if you can put up with it.
Edit 16/6: Price increase from $637.62 to $649.44 (partly/mostly currency fluctuation)
Edit 13/7: Price drop from $649.44 to $641.69 (currency fluctuation, changing continually)
Edit 22/7: Price drop from $641.69 to $635.47
Who him? Yeah guess all the prices will drop, was aware of this but factored it in, hopefully the 2060s won't drop more than 300$ (currently 800$ new), either way you pay a big premium for the top of the line.