That is a good price, and it is available for shipping. Shame they don't ship across the Tasman. Over here Olympus NZ has a big banner on their store.Cheapest I've seen it.
If it works out any cheaper for you, send them a message. They might be happy to make a sale.
Maybe don't click this link then: https://www.camerapro.com.au/olympus-m-zuiko-ed-300mm-f-4-is-pro-black-lens.html
Possibly flow on effect from this: https://www.digitalcameraworld.com/news/olympus-confirms-price-rise-for-pro-lenses-on-01-februaryI looked at Olympus lens prices recently and they've hiked upwards dramatically.
Not sure why.
Our dollar has plummeted, so someone is making big profit.