it is widely available, I ordered mine from a source that I first heard about here called Broadlink. They sell cultivated green kinam chips, and they don't use any inoculation liquid or chemicals on their trees. this involves ordering from China but there are vendors here who carry different types of cultivated kinam which will be pretty similar and maybe closer to you. i have specimens from
@Al Shareef Oudh and
@Maunamoku and kangiiten that are also quite nice.
This material is best heated at low to moderate temperature, does not do so well when it's combusted because it develops a strong wood fiber smell once the oil evaporates.
so I tend to put a few small chips on a piece of mica on my subitism set so that i can just barely see a trail of smoke / vapor rising from the chips. I generally cut them so they are thin flat pieces not chunks