Several years ago we had to replace our coach's radiator. It was leaking at three of the four corners. I found out the stock radiators were made in Louisiana or thereabouts and are renowned for their lack of longevity. Our radiator has two cooling sections - the large section for engine coolant, either antifreeze or ELC, and the small section for oil cooling. Thus, these radiators are rather complex and not cheap.
I ordered my new radiator from the Radiator Supply Warehouse in Sweethome, Oregon. Delivery took a couple of weeks because these must be manufactured; they don't have them on the shelf. The old aluminum radiator weighed about 160 pounds; the new copper, steel, and brass radiator weighed about 260 pounds. The radiator cost was about $4,000 NOT including labor to swap them.
While the old radiator is out, have the repair technicians check the other equipment behind where the new radiator will be installed - belts, hoses, wires, CAC (Charge Air Cooler), cooling fan, etc. My CAC held pressure so it was okay.