in AU there are some nice roller rockers from "Yella Terra" i want a set, they require proper pushrods. nismoparts.com still has:
super expensive oil pan, for what it costs get an accu-sump.
head gaskets - composition and metal - $76
Nismo Race Cam #1 - $190
light weight and oversize lifters
Headers - 1200's use 1 and b210,210,310 use another - $254
you'll need the special gasket, and they may need work done if you're not using a particular intake.

the #'s for just about every proven A series cam are on the internet, so you can get one ground. you may need a donor cam.

Don't get a custom cam unless the guy speccing it has a wall of datsun racing trophies.