Hey Pretty Pastel Please, I don't know about NSW but in Victoria you can actually get custom plates done with Victoria and get USA sized plates. I have a licence plate frame that I can't use and I'm considering it.
Be careful with the valve stem caps. Those cheap ones can fuse to your valve stems in the heart from driving and if yoy ever need air, then you won't be able to remove them. I had to replace all my valve stems because of a cute pink sparkle set