If you go to
Radio Shack, some Wal-Mart Supercenters, Pilot Truckstops, Petro Truckstops, T/A Truckstops, Williams Truckstops, Buckhorn Truckstops, and some others you will find plenty of 13" TV''s that run on 12V. You can also find 13" DC TV''s with VCR''s in them. But you will pay a premium for the 12VDC units.
The reason I mentioned the 13" AC with the
inverter is for cost savings. I have both 13" TV''s that are 12VDC/120VAC with different cords, and a 13" 120VAC. The 12V unit costs significantly more, better than double $$. It was less expensive to purhase a 300W
inverter for $49.00 and the $85.00 TV.
I doubt that the power draw of a 13" tube vs a 9" tube, given all the solid state components is all that different. I think I would put it in the category of negligible. And if your charging system is up to par... there is really nothing to worry about.