Hello Petasplit.
I did some research. Interesting to read about Aravapia valley in SW Arizona where the mother Aravapia avocado got started. No one knows how the one tree got started.
The Aravapia and Stuart improved have the same tolerances for heat and cold. Who knows, they sound like they could be twins.
I did find a place that sells trees.
Shamus O'Learys tropical trees, in Glendale Arizona, on Facebook.
Of course getting it half way around the world ???
If you know someone with a tree, you could get a cutting and graft it to an existing tree.