The Eheim 1260 is probably a good choice then. There will not be much headloss, almost like a closed loop where you take water from the display, circulate it through the chiller and put it back in the display.
Are you sure you really need a chiller versus using fans which are much cheaper and can work quite well when set up correctly. I can easily lower my 100G tank 5 degrees or more with a clip on fan blowing across the surface.