71GMCStepside
Try this link:
http://www.paintscratch.com
At the top of page select the search button.
Then click the link button to search by color name
At the bottom of the display put Radar Blue in the empty box labeled Color name.
Then under make pick Chevrolet.
Looks like it was used on the 93 and up S10's and a different version for the 98 Corvette's.
It is also used on the new SSR's