Heater hose horseshoe spring clip?
 

Does anyone have an idea where one can obtain the metal spring clip for the rear heater hose? This is the horseshoe shaped steel clip which secures the heater core hoses to the rear coolant pipe.

ETKA does not list a part # and sure enough, the dealer says it is not available separately, only with the entire hose assembly.

Anyone have an extra?

That's the spring wire clip for the larger cooling system fittings? Probably try a boneyard.

spring clips are fairly common item .. you should try any serious autoparts store .. or screw the spring clip and put a hose clamp on.