I'll second what David said, most hobby / model shops here don't carry a lot of marine modelling related stock, apart from a few RTR kits. RC cars or aircraft are a different matter, perhaps it reflects the interest in the various modelling disciplines? Most large towns have Model Flying Clubs, but there are nowhere near the number of marine modelling clubs.
We are fortunate in our area, as one of our members runs a model supply business from his home, and he can provide us with many items at a good price. The North Coast Hobby Centre in Lismore, about 30 minutes from us, also carry a small range of suitable products, and is one of the cheapest places in Australia to buy Futaba radio gear. As I have mentioned in previous posts, Float a boat in Melbourne is outstanding for marine modellers.
Peter.