Here's what I'd do.
What you could also add is a fan controller for the radiator fans and use a Temperature Sensor.
Whole thing comes out to be $503.98. The only thing that is missing is the hardware to mount the pump, but that's easy to figure out yourself and save a few bucks. Also with this kit, I omitted a reservoir since honestly, you really don't need it since you'd be running a pretty big radiator and a simple loop. Although, if you add the cpu to the loop, you'd probably would need to add a reservoir just so the water has another location for the water to pool and cool.
You can swap out the hose clamp for the cheaper variant for $.39 each (link
), which is the same clamps used for industrial purposes so you could see how much they are at your local hardware store.