I think its fair to take it on a case by case basis comrade, if you find there are enough substantial communists in the green NZ party it would even be productive to join, advocate for a socialist cause within it, then use the inevitable friction/contradiction of the leadership resisting you to splinter off any socialist/anarchist membership you network with.

I also have 0 clue where to start with NZ and socialist organizing… The palestine cause and its open support would be enough for me to support them if nothing better presented itself, I understand your reasoning.