Sound machine suggestions

Okay so we have a sound machine that we absolutely love. It can play all night and has a projector with all different options like under the sea and space etc... the boys love it and only seem to sleep well if it's on for them.

So we are planning a camping trip in the upcoming weeks and I need a portable sound machine I can bring with me, because honestly I dont wanna try going without it lol.

Anyone have any good suggestions for a portable sound machine that can play continuously for the whole night? Bonus if it isnt super expensive lol.