On board television
Another possibility is to get a player designed for automotive use. Such players generally run in the 150-200 buck range and you can get 110V players for 30 bucks though.
My other thought is to simply get a small inverter that can supply the minimal needs of such a player/screen, and wire it into your 12V system. This will be a bit more versatile and let you take advantage of whatever 110V products/prices you like.