Hi Tricia, transporting tree ferns between countries has become much more difficult over the last 20 years. I would think that if there are any Botanic Gardens or significant gardens in Australia with collections of ferns, they would be your best option. That way, you won't have to jump through hoops and you have a better chance of getting them fresh (and therefore having silver on them). Also, are there specialist fern nurseries in NSW or Victoria who might have plants ?