Does Buddhism have a significant notion of justice
While I can relate to this somehow, it overlooks one striking and most basic fact of Buddhism: that justice is a law of nature.

In contrast to Greek thought, this means, that the Greeks, since their concept of "the world" or "the universe" was rather empiro-scientific and unrelated to moral (=human) values, had to look for "human" justice or even "define" justice.

In Buddhism (and India in general), the very law of nature is a moral law, the law of kamma/karman. Consider for example the Paṭiccasamuppāda/Pratītyasamutpāda, which can be viewed as a formulation of the Buddhist law of nature or the kosmos, the universe etc.: everything here is treated as subject to cause/condition and effect, without beginning and end. The important thing to notice is that causation is moral causation by good and bad deeds.

To conclude: since the kosmos is just and takes care of retribution, the religio-philosophical thinkers did not have to elaborate differing visions of justice. It is not the humans, that have to take care of it. Seen from this angle, justice is (implicitly maybe) at the very core of Buddhism.