You could try Ponto Falls Reserve, though Google Maps says it's a 40 min drive. There is lots of open space up away from the river. I observed from there one night: dark, great northern horizon, plenty of campers but their lights didn't bother me (and they were in bed early). The only issue was that it is very open and the night I was there the wind nearly blew the car away
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https://www.google.com.au/maps/@-32..../data=!3m1!1e3