yes, there are alot of injector shops that will upgrade your stage 1's to stage 2's.
I am in the same boat you are and will be going with Rosewooddiesel.com.
I think its 400 for the nozzles and 150 for the install and flow test. I think that is the price for 80% and 100% over stock nozzles.
My goal is to break 400 hp, so i will probably just go with 80% overstock, which should be good for 425hp with a good turbo, HPOP, and electric fuel.
I would go with larger nozzles, but i dont want to kill my trans, it is modded, but the shafts are still stock and over 400 hp is when you can really break a shaft pretty easy.