In a previous article we introduced the concept of restricted Nmatrices (in short, RNmatrices), which generalize Nmatrices in the following sense: a RNmatrix is a Nmatrix together with a subset of valuations over it, from which the consequence relation is defined. Within this semantical framework we have characterized each paraconsistent logic C n in the hierarchy of da Costa by means of a (n + 2)-valued RNmatrix, which also provides a relatively simple decision procedure for each calculus (recalling that C 1 cannot be characterized by a single finite Nmatrix). In this paper we extend such RNmatrices for C n by means of what we call restricted swap-structures over arbitrary Boolean algebras, obtaining so a class of non-deterministic semantical structures which characterizes da Costa's systems. We give a brief algebraic and combinatorial description of the elements of the underlying RNmatrices.Finally, by presenting a notion of category of RNmatrices, we show that the category of RNmatrices for C n is in fact isomorphic to the category of non-trivial Boolean algebras.