i was looking into kamagong sticks a while ago, and contacted these guys who were pleasant to deal with. I asked if their ironwood came from a sustainable source, ie. if the suppliers were commited to replanting, not just de-forrestation. they said that they were not sure, and that, tbh, it had never occurred to them. They said they would find out for me, but in the end could not find out themselves. This was 2 years ago, so they may have that info now.
i decided against purchase as the tree is very rare and being over harvested as it is. To be part of the solution, one has to choose not to be part of the problem.
Kamagong is heavy and not a good choice for training. Many schools wont let you use them anyway as they destroy other classmates rattan sticks. I would stick with rattan, but its your choice.