Cistus stocks some items that are pretty much exclusive to them in this region (if not all of North America), this might be one of those. They are sometimes the sole introducer of particular plants to local gardens, as Colvos Creek also sometimes is and Heronswood used to be.

I got mine from Cistus!

I could be wrong, but I think you're unlikely to find it anywhere else for the present. I would grab that wherever you can while you have the chance!

There used to be one in Wright Conservatory in Tacoma, but I'm not sure what became of it when the place was remodeled - I didn't see it there on a recent visit.

Here is a link that might be useful: More hardy Scheffleras

just picked up one at the hardy plant society sale.

$32 for a tiny lil guy. i am thinking woodland shade, north side of house under deciduous trees.

what has been people's experience with the plant? any problems these last few winters? how long has it taken to throw up those huge flower structures?