gostwyck postcode nsw Home ›› Postcode Finder ›› NSW ›› Gostwyck Gostwyck local listingsThe suburb of Gostwyck is located in NSW and has a postcode of 2358. Free gostwyck business listing! Get the first free listing in gostwyck! Search and find other Postcodes in New South Wales or widen the search to Postcodes in Australia.