Buying the best watercooling system under $350...need help

I have an amd 4800 (2.83ghz) and two x1900's in crossfire and I am going to order a liquid cooling system but all the the configurations that I have come up with dont match in tubing sizes nor do I know if they are compatible. My brain is fried at this point. I would like to order it by tomorrow morning but only if I am sure that I found the right one.

I would perfer one that is external because of space in my case. Also I dont really care if I have a pump, radiator, etc. just sitting outside of my case not in an enclosure as long as it will not affect the performance. Thank you in advance for any and all suggestions/help.

Also I can go above the $350 if there is a substantial difference.