Bingo!
Fedco 2-224 heater core $29.98 at PartsAmerica
Looks like it should work with the coolingworks shroud, inlet/outlet clearly have a perpendicular-to-the-core run before bending, appear to be round section.
EDIT: Just ordered one from PartsAmerica $36.51 to my door. Will be out of computer touch until Monday-next, but will try to post results then. Blackstealth, sorry for the delay - this is the best I can do for you...