i found this add if it helps , fruit and nut trees not found elsewhere in Thailand (Chiang Rai, Chiang Rai)
Posted on: Sunday, 10 February, 2008 08:17
Updated On: Monday, 11 February, 2008 07:09
Expires On: Tuesday, 20 May, 2008 09:17
Reply to: firstname.lastname@example.org
....neither will you find such fruits and nuts in Thai markets: I sell the following trees, ready to plant: grapefruit, mission black fig, brazil nut, macadamia nut, avocado and others. Also can sell blackberry starts. http://wonderfull.com/garden-fruit.htm
for added details.
Can ship within Thailand - and possibly SE Asia (not sure whether it's plausible to ship to places outside Thailand).