Kelley Blue Book does not have listings before 1992; if you check their car value link it only checks car values from 1992 to 2014.
To give you a guide we found 1978 Plymouth Volares For Sale at Vast.com for $3,800-$8,999; a 1978 Plymouth Volare station wagon from Applegate, Michigan at $3,800 and a 1978 Plymouth Volare - True Super Coupe at $8,999.
Looking to drop some money on classic cars? It might be a crazy bargain, or it could turn out to be a colossal waste of cash. Unless you know what you're doing, there's just no way to tell. Check out some tips on buying classic cars at Mensjournal.com.