Everything from the eucalyptus tree is bird-safe, and pretty much all of it is part of the diet of many Australian parrot species. It's generally considered to be beneficial to non-Australian parrots too.
There's a place in California selling eucalyptus products for birds at
http://www.eucproducts.com/index.html I haven't tried any of this - instead I planted my own eucalyptus tree. I can do that because I'm in Arizona, where the climate is fairly similar to the Outback. I see that you're in Michigan, where it would be much harder to grow your own!