smaller heatercore

Well i sold all of my watercooling gear minus one piece, and now i am looking to set up a small water cooling setup. What is the smallest heatercore there is right now? I had the Chevette heatercore and for what i am wanting to do it is to big i need one that will be a little bigger then an 80MM fan so i can mount it to the top of my case. If anyone has any suggestions let me know. I have looked around and cant really find anyting for the size i want.

Lotec