Answer: I'm sorry you are having a hard time finding this tree. It should grow fine in zone 7, it is rated hardy from zones 4 through 9 and magnolias tend to do well in your area. You might want to check with nurseries that carry monrovia (and other products) in your general area by using the zip code search at the Monrovia web site,
Generally speaking, nurseries in larger cities will carry a broader selection of material. If they do not have it in stock, perhaps they could order one for you.
Alternatively, mail order nurseries may offer it. One that is currently listing it is Roslyn Nursery
Good luck with your search!
Q&A Library Searching Tips