  In this paper, we present a model which attempts to unify a new dark sector
force with a local $SU(3)$ flavor symmetry. Dark Matter (DM) and its potential
interactions with the Standard Model (SM) continue to present a rich framework
for model building. In the case of thermal DM of a mass between a few MeV and a
few GeV, a compelling and much-explored framework is that of a dark
photon/vector portal, which posits a new $U(1)$ "dark photon" which only
couples to the SM via small kinetic mixing (KM) with the SM hypercharge. This
mixing can be mediated at the one-loop level by portal matter (PM) fields which
are charged under both the dark $U(1)$ and the SM gauge group. In earlier work,
one of the authors has noted that models with appropriate portal matter content
to produce finite and calculable kinetic mixing can arise from non-minimal dark
sectors, in which the dark $U(1)$ is a subgroup of a larger gauge symmetry
under which SM particles might have non-trivial representations. We expand on
this idea here by constructing a model in which in which the dark $U(1)$ is
unified with another popular extension to the SM gauge group, a local $SU(3)$
flavor symmetry. The full dark/flavor symmetry group is $SU(4)_F \times
U(1)_F$, incorporating the local $SU(3)$ flavor symmetry with PM appearing as a
vector-like "fourth generation" to supplement the three generations of the SM.
To ensure finite contributions to KM, the SM gauge group is arranged into
Pati-Salam multiplets. The new extended dark gauge group presents a variety of
interesting experimental signatures, including non-trivial consequences of the
flavor symmetry being unified with the dark sector.
