https://www.amazon.com/Moving-Liquid-Picture-Sandscapes-Painting/dp/B09QLSBYF1
but it can get absolutely wild once you get in the scene, some of these guys are paying insane prices, up to $1-2k for a wall piece
https://www.oceanofferings.com/black-beauty-moving-sand-art.html(http://www.autoadmit.com/thread.php?thread_id=5373975&forum_id=2\u0026mark_id=4295921",#46556455)