my vote -
build it back up to normal with some forgies and cams...and then put some nicer bolt on's on. the only thing a rebuilt engine will give you is reliability - not power. the power comes from the bolt ons.
the engine rebuilt should be able to handle a bit. as paul said...build it up properly - but dont spend rediculous amounts of money on combo's etc...jsut more hassle than its worth...especially when you can get what you want from the 2.6
from there you wana do research on what combo of bolt ons......turbos, ecu, injectors, etc etc etc.
i would recommend you take a look at this thread RB26 dyno results. ....take a look at the third post - if you were to add on some turbos, a front mount, injectors...somple things...you should safely hit 300 +
as paul said...you dont need to spend massive money...jsut do it simple and you should be fine...dont mess around with un - nessacary things.
hope that made sense...and feel free to ignore me