New Zealand has published GPS NPA to offshore installations, though they are vaialable to "approved" operators only. The MAPts are offset 45 deg from the platform at 0.9nm. The OCHs are in the region of 250-290ft with vis. of 2000m required.
The operators also have NDB/ARA procedures in their Ops Manuals. With radar altimeter, the minima are even lower (vis. down to 1500m - 1000m under certain conditions)