I would think in your area there must be somewhere that has an old style radiator shop. I know there are not many any more and I frankly miss those days but the ones still in business most likely may be good. Do a search and check out the antique guys. These are not that old comparatively . If you don't care about originality then there are many possibilities.
A price of 500 would be great ,,my wife's 2011 Jeep grand Cherokee's rad would be 1000.00 Pay the price at a good place and be done with it. I do not know about C bodies but with my 86 glhs Omni I went from a 2 row to a 3 row,,,or was it a 3 row to a 4 row ,,I cant remember but in any case ask if there is an upgrade with the stock size. If it were me I would want it stock looking.