  Scenarios in which right-handed light Standard Model fermions couple to a new
gauge group, $U(1)_{T3R}$ can naturally generate a sub-GeV dark matter
candidate. But such models necessarily have large couplings to the Standard
Model, generally yielding tight experimental constraints. We show that the
contributions to $g_\mu-2$ from the dark photon and dark Higgs largely cancel
out in the narrow window where all the experimental constraints are satisfied,
leaving a net correction which is consistent with recent measurements from
Fermilab. These models inherently violate lepton universality, and UV
completions of these models can include quark flavor violation which can
explain $R_{K^{(\ast)}}$ anomalies as observed at the LHCb experiment after
satisfying constraints on $Br(B_s\rightarrow\mu\mu)$ and various other
constraints in the allowed parameter space of the model. This scenario can be
probed by FASER, SeaQuest, SHiP, LHCb, Belle, etc.
