I’ve had excellent results with stuff from lederzentrum.ch see Seat leather repair kit? for an example of their leather paint. They also sell a touch-up kit which is just a dye - find for correcting areas which are just buffed/faded.
Both work great on leather. Not so sure about vinyl.
EDIT: more pics at https://plus.google.com/u/0/collection/IVbhqB, see the album “Seats”.