Lee ---Mr. Lance Walker sells quality rebuilt starters. He's a HET member and is located in North Carolina. His email is hornetllw@yahoo.com

I think Lee would want a source in Australia, as shipping from the USA would be prohibitive.  

Lee, you should be able to get your starter rebuilt by a starter and generator shop locally to you.  

Thanks for your help  Lee

i have the following starter for my 12v converted 1953 hornet - the original 6v starter did not like 12v - the modern starter is much lighter - here in the usa, places that rebuild old starters are getting harder to find -  https://snap-usa.com/products/hudson-hydramatic-mini-12-volt-starter-replaces-mch6107-mch6204-1951-1954 - hope this helps

That’s what I bought 2 years ago. Works great. Putting 12V into the original 6V starter broke it.