After finding out my radiator was leaking, I ordered a eBay special China radiator. Bought one for my S15 and it was pretty decent, especially for under $200. I ordered the 52mm dual core aluminium design for a low low cost of $175 delivered to my door from Melbourne.
Also I took my valve cover and water outlets to get blasted at Chilton Engineering, they turned out looking brand new! Much better then paying over $300 for brand new items through Mazda.