There is no way to know exactly what GM branded vehicle that the handles were sourced from, and there is no part numbers casted into the inside of the handles. There is no doubt that the handles were used on some other GM vehicle, but only extensive research would reveal that information, and I don't know of anyone that has ever undertaken the project of determination. The Miller Meteor parts book indicate the original GM part numbers for some components, however, the outside door handles are not listed with a GM part number, only the Miller Meteor part number, which is of no use today, other than to distinguish handles from year to year.