... my nebulite boxes? Or in other words, at what price do you personally think Nexon will sell them from NPCs?

I personally don't think it'll go lower than ~500k, because any lower than that and the market will be completely flooded with D/C/B nebs: exactly what Nexon was trying to prevent when they nerfed the drop rate of the original boxes into the ground.

Obviously, we don't have any information other than the fact that they'll be available in shops sometime after January, but give me your best speculations