We have a large selection of pumps specially designed for use in PC water cooling systems. We both have pumps with reservoir and pumps without reservoir, so you will certainly find a pump that fits in your water cooling system.
CoolerKit recommends: It can be difficult to figure out which pump to choose. For high-performance systems we recommend Swiftech MCP35X or Laing D5 (eg. Alphacool VPP655). For less demanding systems we recommend the EK - DCP 2.2 pump.