Depends on how far out of Port you want to travel. I would look for somewhere just south between Lighthouse Beach and Bonny Hills, I'm sure you can find a school oval or something. Or head west and look for something between Port and Wauchope.
I have observed from my parents balcony in Lighthouse Beach, south of town, and the skies were pretty dark. There is a park in Lighthouse Beach which might be OK but I'm not sure about street/house lights around there.
Sorry I can't help you with specific spots, I grew up there but I wasn't into astronomy back then.
Google Earth/Maps is your friend.