I use a Northern Radiator. Cheaper, but still good quality and cools well. Mine was actually a cross-flow meant for a Hemi 'Cuda. The size was right and fill neck was in the right spot so we turned it sideways and it works great. I just went through the Northern Rad book and figured out what would work based on the measurements.
I'm going to tell you right now you shouldn't be looking for a 3 or 4 row aluminum. That's just knowledge of copper/brass rads you're using but aluminum rads are different. Because aluminum is stronger than copper/brass, the tubes can be made much thicker, so they flow and cool better partly because of this. Most aluminum street radiators will have two rows of tubes somewhere in the 1.25"-1.5" range. So don't be hung up on two-row aluminum radiators, they're great.
