Nice to hear.
It's likely like the other Disney-owned films released in Oz (Splash, Turner and Hooch, Quiz Show, et al)... region-free and strangely absent from US releases.
Think I'll go order me one. Haven't seen the movie in a few years and I want to.
My guess is that with their push for streaming and their subjugation of most Disney-branded catalog titles to the Movie Club, they want the Australian division to do the heavy lifting with titles such as Opus. This is similar to how they let the UK rights holder of Flight of the Navigator release it on Blu-ray and then re-release it with oodles of extras. Except unlike that one, which was a pickup from Producers Sales Organization (who also made Short Circuit), this and the other movies you mentioned are ones that I believe they own outright and weren't co-productions or independently produced titles they picked up here and there.