Some people get these enclosed type (so the sand doesn't spill everywhere) but they're not cheap and there are other types - or just a pyrex dish! They are quite space saving I guess. You can also get a salt pig that is similar
https://www.amazon.co.uk/Kaytee-Cera...ateway&sr=8-47
https://www.amazon.co.uk/WM-Bartleet...kitchen&sr=1-6
I have this one for our robo which is nice. A bit more space to dig and roll in and a half covered roof to stop the sand coming out of the cage! The trouble is the postage adds to the cost.
https://www.rodipet.co.uk/houses/rod...sand-bath.html