I'm making some on the pottery wheel. LOL. Not super cheap, but great fun.

You can use almost anything that will cover the snake. Flower pots with doors knocked out, plastic bowls, margarine tubs, etc with doors cut in the sides or top. Disposable cardboard boxes! Opaque juice or milk jugs, cut apart the end off and a doorway.

Just be certain that any cut area/surface is not sharp. You can rasp the edges of pottery, using a heavy nail file, or any metal file. The edges of plastics can be melted gently with a flame, hot butter knife, or filed as with the pottery.

Be certain that top openings are wide enough for your snake, and as your snake grows, keep an eye that it is not outgrowing the doorway.