64 Dart Armrests, measurements please.

I trying to buy new armrests and bases for my 63 Dart. Nobody makes replacements for a 63, so I am going to use 64 (close enough) But I need to know what length they are. Iv'e seen 10", 13" 15". Anyone with a 64 GT, could you post some dimensions for me ( front & back) Thanks.