Parallel-flow condensors are more efficient than stocK: http://www.ackits.com/c/Parallel/Parallel+Flow+Condensers+-+Aluminum.html But they are universal fit.
I got a universal aluminum one from Summit for the Riviera. All depends on how much fabrication you're willing to get into. There are also larger aluminum ones from later model cars but the Riviera's narrow downflow radiator limits my core width which drove me to the aftermarket. You should be able to find one off of a 90's B-body or an H-body FWD car that would work if the outlets were on the correct sides.
Hard to beat ackits on price/quality. I've got one of theirs still in a box, waiting for whenever I have to mess with the a/c - then I'll swap it in.
With those prices for new ones it's not worth my time to go and pull a used one. I guess I will have to go measure and see what the biggest condeser I can squeeze in there.:TU:
