Here is one I made from a black 1 gallon bucket that I bought at Dollar Tree. It cost me, you guessed it, one dollar. I just cut the bottom four inches of the bucket off and put a mouse hole shape in it. It may be just a little bit big for a hatchling but you could always crumble a little paper up and put it underneath to take up some of the space. It is also dishwasher safe if you put it in the top rack.