You can contact Alphacool to get custom radiator, but it will cost you 80,000 USD! It is because of the high costs for their machines. I think that HardwareLabs may help out. If not, try to find some radiator maker for cars, trucks etc. that make copper radiators. They will be able to do a custom model for you.
As far as GPU block, you can contact Alphacool too. You need to send them a GPU and they will provide a block free of charge. But only downside will be their
dual slot design.