Recommend a battery powered amp?

My wife and I are traveling to China and Japan over the holidays. With the length of the flights we're purchasing a few items to keep ourselves entertained (128gb microSD cards + a portable SSD chock full of movies), one of the things we wanted to get was an AMP for the trip that had 2 headphone outputs that we could control individually.

For headphones One of us will be using a pair of Audiotechnica ATH-M50s/LE headphones, and the other will be using a pair that is tbd (most of our headphones are open back, not the greatest for flights, so we'll be purchasing another pair of cans for this trip)

I'm not that deep into the audio world, but could probably spend up to $150. The reason for 1 amp with 2 outputs being we would like to watch some movies together during the flight.

If this is unreasonable then perhaps a Y splitter + 2 small amps would be a better solution? If we have to 2 I could probably bump the budget up a little, but staying at or below 150 would be preferable.

Devices we'll be using these with are:

Samsung 10' tablet
Razer Blade
Macbook Pro (it's ok, its running ubuntu i swear)
Nvidia Shield Tablet
Nintendo 3ds

Creative X5 will suit your needs.