Just as a reference, I just checked my Fire Mountain Gems
catalog (the 1999 Jewelry Maker’s Catalog), and according to it,
they don’t carry blue onyx. However, I suppose there is always
the possibility that they have some in their warehouse. You can
always call them and ask. 800-423-2319.
Hope it atleast helps a bit.
-Cortney Mayle in hot 'n humid Pittsburgh, PA