What's wrong with yours? Modine is the manufacturer of the original, I'm sure it's been copied by many. Then it's just a matter of matching up the hoses....
Checked with Pontiac dealer,NAPA,Advance Auto,Autozone, no luck. GM parts direct shows it to be obsolete item but I E-mailed them and they are suppose to be inquiring further. Also talked with Modine MFG.Co automotive division and came up with nothing. So if I do find a source I will post it, but does look to good. I think I'll not worry about it cause I can't see how much the little bastard could cool the oil anyway.