  We report on the determination of the improvement coefficient $c_{\rm A}$ for
the non-singlet axial-vector current $A^{a}_{\mu}(x)$ in the framework of
stabilised Wilson-Clover fermions within three flavour lattice QCD. This is
done by requiring the PCAC relation to hold for two different pseudo-scalar
states. To generate these states, wavefunctions altering spatial structures on
the boundaries of a Schr\"odinger functional lattice are employed and some
variations of the (previously applied) wavefunction method are explored. The
improvement coefficient is determined on a few ensembles for a range of gauge
couplings that is potentially useful for future applications. Preliminary
results on the renormalisation constants $Z_{\rm V}$ for the vector current and
$Z_{\rm A}$ for the axial-vector current are also presented.
