EASY to drop the price: Ditch the liquid cooling and drop the CPU down to a 6600. I'm dead serious. You don't need liquid cooling. And if you think you do or are entirely enamored by it, your setup has a few problems as well:
-An 80mm rad with a 655 pump is a BAD idea. BAD BAD. That pump will put too much heat dump into the loop, plus an 80mm rad alone for cooling isn't good enough for your CPU and GPU loop. End of story. A high end air cooler will do better. You cannot use a huge pump like that, do a CPU and GPU loop, and only cool with an 80mm rad. A 120mm rad would the ABSOLUTE mimimum, and even then I shudder to think about it. A 2x120mm or a full 240mm rad is needed.
-Why the Koolance blocks? CRAP. Especially if you're intent on spending the money. And are you sure it fits on the vid card too? You should double check, I can't remember offhand.
-A GPU and a CPU/RAMsink block? Why both? Either one or the other.
You asked. Sorry if it's not what you want to hear, but it's the truth. Ditch the liquid, get a 6600, and pick up a Thermalright 120 Ultra or Extreme air cooler. Seriously, you'll do just fine. Then with the money you just saved, jump up to an 8800GTS 320, and you'll be ALOT happier and still save money with a better system overall.
8)