HQ walnut logs (level 25 node I believe) sell well. There's a Carpenter leve that asks for 5 of them, and since you get double the xp for HQ synths, people leveling CRP's are always buying the HQ logs.

HQ stuff in general sells for more, and npc's dont sell them. So crafters are always buying HQ mats for levequests. HQ items also give more xp, so use your Leaf Turn/Leaf Turn 2 for max profit/xp.