Silver or gold?...
1oz Dragons were popular so they sold the entire mintage and should be pretty easy to find. The more obscure animals that no one wanted are the ones that seem to be most expensive. I guess people are trying to complete full sets so are happy to pay whatever the going cost is.
Actually pretty sure all years had fulfilled the 300k mintage. They just minted a lot of spin-off dragon coins which diluted the market. Perth Mint were also selling rolls of dragons for $1000 per roll ($50 ea.) at launch, so a lot of people are reluctant to sell anyway since the market has priced them below most people's cost.
You are right of course! it was the other sizes that were unlimited but unpopular in the other animals.
https://www.perthmint.com/documents/Mintages/Bullion/The Australian Lunar Silver Bullion Series Two 2008 - 2020.pdf
I remember that they made an additional 200,000 1oz Dragons with a lion privy along with all the coloured, high profile and other versions.