  We use polarization-resolved Raman scattering to study lattice dynamics in
NaFe$_{0.53}$Cu$_{0.47}$As single crystals. We identify 4 $A_{1g}$ phonon modes
at 125, 172, 183 and 197 cm$^{-1}$, and 4 $B_{3g}$ phonon modes at 101, 138,
173, 226 cm$^{-1}$. The phonon spectra are consistent with the $Ibam$ group,
which confirms that the Cu and Fe atoms form a stripe order. The temperature
dependence of the phonon spectra suggests weak electron-phonon and
magneto-elastic interactions.
