Martin -

I have had decent luck with radiators from a salvage yard. The 240 radiator is the same as some of the 740 series, and practically any one will fit, provided that the transmission cooling lines are correct.

The older models had metal end caps, which break less frequently than the plastic cap abominations. Since you don't have an emergency, that is a low-cost route. Find a young one, get a radiator shop to clean it up, and have it ready. BTW, 1983 and younger 240's have a tag on the rear edge of the driver door stating the month/year built. Helpful in a boneyard.

Anti-freeze?? Use a good brand, always use the same brand, and dilute with steam distilled water only. Dilute for the maximum protection as on the label. If you need to add water at any time, overheating, etc., limp to the nearest grocery and grab 2 gallons. Low cost and useful elsewhere.

Best Luck,

Bob