I'm looking for a 49 key keyboard with sounds for my son to take traveling. He's in his third year of classical lessons and usually practices on an upright. I personally have luck with a little controller I take on business - good enough for hands separate practice, and such a wonderfully awful action that if I can nail a passage on it, transfer to a piano is easy.

But when my wife - who as a teacher shares the same vacation schedule as my kids - takes them places, she's not technically adept enough to manage to operate a cordless drill, much less a controller. One of my kids is absolutely crazy about the piano and wants to practice all the time, and he's begging me to find him a little keyboard to take over spring break. Hard to say no to that, but...do any exist? I don't care if it is synth action, but I don't want mini keys, or anything so expensive it would crush us if damaged in transit, and it seems everything I can find is either very expensive (>$650), or very cheap (<$50) with an unplayable action (e.g. keys get stuck together), or a controller.

I'm thinking a cheap controller paired with a small piano-only sound module, like the Alesis nanopiano, but that can power the controller over a USB cable. Does such an animal exist? Is there a better way?