As far as the rev range, the argument can be made that CA's have more potential to be rev happy than SR's. Definitely going to need a nice head/valve job to get there though.
As far as the numbers and throttle response, like he said go forged. Lighter internals=better throttle response and less chance of detonation. If you really want that throttle response possibly bore .20 over.
I would go v-mount, very short piping, efficient setup. Can be expensive though.
For something like this I would suggest going the dyno tune route. You'll get the most out of your setup as long as the tuner is experienced. If you do a Mail romtune make sure your very very specific about your setup and your goals.
Manifold:
Nissan CA18DET Custom Turbo Exhaust Manifold Sales on TurboClub.com Global - Home
I think it's like $330 or something, in my opinion you should at least have a good port on the stock one or upgrade to something like above. At 300whp + i really think it will be helpful.
Injectors:
Deatschwerks
^^^^^Only linking there for their fuel calculator. Check it out, might help you with size.
I'm thinking somewhere in the 500-600's. Maybe a little more. As far as making the injector's fit, I'm not a CA guy, search for it.