Crow,
Depending on the shop, and depending on if they will work with you, I have had 4 core rads made, (not
for the zuk) by having tanks the right size, and they can add a core to near any size. Then take the zuke
brackets and solder them on. Tanks are the key for most shops. few will stock tanks, it's just not worth it.
The other way is to go thru a catalog, and find a radiator the physical size you need, and have the brackets
moved. That may not be cost effective, and will definitly kill the warrenty.