"non-aggression itself isn't a priori true"
Meaningless. "Non-aggression" (and Zero Archation) is the best way to attempt to live among others so far discovered. That doesn't mean it is "true", or that it isn't based on something more basic. The alternatives have been tried, and anyone who bothers to observe can see where they lead. The results are true. The principles are true, as far as they work and the alternatives lead to ruin for our species.

You can behave as though rights (not specifically "non-aggression") are reciprocal, but that is still treating rights as though they are privileges, granted or withdrawn on a whim by someone who believes they have that "authority". I still recognize that murderers have rights, even though their rights don't negate their debts.