Calling the ethics as described above "deontological" is risky and ill-advised because that term is commonly used to describe Kantianism and a use of the categorical imperative[1]. These two (if taken seriously) rule out a marketplace because participants treat each other solely as a means to an end. Deontology, as it is commonly referred to, and the NAP are incompatible systems of ethics.
My understanding was that 'deontological' simply means (indeed, almost literally means) having been derived from rules. Deont being the Greek to refer to duty or rule.
Kantianism is probably the most famous from of all the deontological ethical systems. But structurally the NAP and the categorical imperative serve the same purposes in Kantianism and nirvana's libertarianism, respectively: they provide the principle by which all other actions are held to account.
Except that Kantianism is by no means the only form of deontology, and in fact has nothing to do with any of this.
I do _not_ mean deontological in a derogatory sense. I mean it descriptively in contrast to consequentialism.
Edit: To quote your own source, "The non-aggression principle, also known as the non-aggression axiom and zero aggression principle, is an ethical stance which states that any initiation of force is illicit and contrary to natural law. It is the basic moral axiom of deontological libertarianism, most upheld by philosophers such as Robert Nozick and Murray Rothbard.[1]
[1]: http://en.wikipedia.org/wiki/Deontological_ethics#Kantianism