I like Chemical Guys Black on Black - LINK
Just spray Fade 2 Black on plastic, rubber and vinyl pieces and it quickly restores a deep black finish. Use it on your dashboard (I wouldn't suggest it on the interior), doors, arm rests, bumpers, door handles, engine bay (hoses, casings, etc.), exterior trim, mirrors and so much more. It is especially popular to use on the wheels because the spray evenly covers this tough to reach area with a like new appearance. It prevents fading and other damages with one easy application. Hold the bottle 8 - 10 inches away from the surface and apply a light spray. If you want a deeper and darker shine apply a second coat, but one is usually perfect for most detailers. Within minutes it is dry to the touch without that greasy and oily feeling. Just spray it on and walk away.
Other options...
Poorboys Trim Restorer - Works great on pretty much anthing you throw at it - LINK
Locally, you might find Mothers Back to Black at Autozone or something - AMAZON LINK