Fred,
I'd like to take credit for those little suckers but they were part of the shroud when I purchased it. I bought the fan and shroud combo from Vintage Air in San Antonio. Here's a link to their online catalog:
http://www.vintageair.com/catalog.asp
Look on page 70, part number is 34317-VUF. CFM rating is 2700.
The dimensions are just right for the Lone Star radiator by turning it sideways and doing some real minor triming.
I fabricated my inlet shroud from a piece of aluminum that Lone Star had sitting around and I don't recall the thickness. It was brushed and I just polished it.