Lacquer would be factory correct. Also, I would discourage you from just lightly sanding and painting over top of the previous. I believed it is far better to remove as much of the original paint on the interior metal as possible (especially the door). This will lead to a better overall adhesion.
I have had good success with the lacquer rattle cans from NPD and VA Classic Mustang. As Charles states, apply a dusting coat as the last coat to get the desired eggshell finish.
Regards,
Pete Morgan