1967 Dart GT Convertible How Rare is it?

This is info is from Automotive Information Clearinghouse, in 1993 they say there where 582, 1967 Dodge Dart GT Convertibles left with 4 of those being in South Dakota. Don't know if they are still in business, but for $15 they would send you a sheet telling how many of a certain year make and model of car left.