+1
Aren't GTR Rods and GTST Rods the same? Its just the pin/deck height of the piston that changes?
Anyway, get some GTR rods (or use stock if they are the same) and replace the bolts with ARP2000 bolts. New ACL or good bearings of your choice, and CP pistons (could also use JE, wiseco, etc etc, but CP are good).
If you want to replace rods then either Eagle or Spool are good for money, noting wrong with the brand names like Tomei, etc etc.
If you search on Ebay America you can find CP and Eagle Rod combos for less then $900 I think, ARP2000 Mainstuds and head studs would be a nice addition also.
But if you are only after that power range, you shouldn't need a built motor. Stock is generally good for around 260-300rwkw (350-400rwhp), just upgrade the ECU, Injectors, Fuel Pump and Turbo.
Check out the RB25 Dyno thread and see what power levels people are getting and what mods they have, link.