Check out ebay if you're looking for an OE one. I think the Eagle Aluminum ones with a lifetime warranty are much better at performing their function. My '72 240z came with a 280zx radiator installed by the previous owner. It sat much lower towards the ground and the outlet was in the incorrect direction. Here's a picture of the aluminum 240z radiator (silver) I purchased compared to the 280zx (black).
More pictures of the aluminum radiator install: Dave's 1972 Datsun 240z: Radiator Upgrade
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