i replaced my original with one from
Universal Parts Inc. (www.universalpartsnc.com) it bolted right up and the cooler lines were right on. a little pricey, but it does the job. runs about 165 with a 165 thermostat. it's aluminum. part # CR3207. desc.-62-65 nova downflow radiator with cooler. top & bottom rh hose connsctions.
$489 + $40 shpg.
there is a couple other post about this already but here is mine. i believe it is a 19x24" with a 16" fan. i went with this one to utilize the stock mounting holes in the suport. i welded the tabs on my self to the tanks. as you can see it works perfect. this is also cooling a 13.5-1 SBC and usally stays around 185 on a average day here in Cen-Cal.