And then buying a decent 350-400LPH pump, a small acrylic res, and a single 1x120 or 140 rad. Put a fan on it and call it a day. Don't forget tubing/fittings/liquid.
They're 60mm fans and I wouldn't swap them for quieter ones because you have the possibility of reducing airflow. I'd check out the cooling modifications section of this page for some ideas. http://forums.xbox-scene.com/index.php?showtopic=471958
Smaller fans that move a lot of air are never really quiet. The thing I see is the intake venting is not all that great and wonderful. Any way to mod that?