I never had much luck finding a pin spanner, but I did find the right locknut socket on the internet. But this was for a 1997 Pathfinder, not sure if it will fit your year. If you search for OTC7698 you should find it, here's the page I got mine from a few years back:
http://www.handsontools.com/store/li...roduct_number=
There's also a CTA4170 tool but I couldn't find it in stock anywhere back when I was looking. Some people have bought a similar GMC/Ford locknut from the local auto parts stores and grinded the pins to fit.
By the way, you won't need the tool to get the locknut off, it will come off easily with a tap. You only need it to seat the bearings when you reinstall the hub.