I was always told to wear what you would wear to work to an interview. I grew up in country Victoria and I can't imagine anyone wearing nice pants and shirt in a caravan park. I'd say to dress neat casual. I guess it's hot down there at the moment too? I'd wear a nice summer skirt (long if you want to be conservative) and a nice top and for hubby shorts (dressy kinda ones) with a shirt but not a formal dress shirt, just a nice shirt with a collar like you'd wear out for dinner during the week. If it is cold I think pants would be fine but not necessarily jean or black pants. Do you have any full length pants made out of different material?