Lack of Prunus Serrulata (East Asian) Cherry stock

[Bonsaidoctor]

Having recently just visited Japan, it is hard to miss how crazy the culture is about Cherry Blossums. When I came back to the states, I thought I would get some Prunus Serrulata stock (pre or created bonsai). But I an struck by the dearth of supply on the internet for either pre-bonsai or bonsai. (Lots of seeds for sale).
Does anyone know why- are they hard to grow? Just not much of a demand? Before I look for young general nursery stock to “scratch this itch”, I want to make sure I am not overlooking something. Thanks as always

 

[Jzack605]

They're popular enough in the landscape, maybe you can air layer or take some cuttings from a friends tree. Hell They're used in public spaces here enough you could easily find one and get some cuttings from that.

I want a Black Cherry bonsai. They grow wild so with a little searching a Yamadori is definitely possible.