I forgot that you're not in the U.S.- the "cm" should have reminded me. You can also make disposable hides (dump when dirty) out of cardboard boxes- things like cereal or cracker boxes are about the right height & dimensions, until you find some good permanent ones that work for you. Use what you have available- your snake won't care- only if he doesn't have them. Some people modify plastic containers they buy (like for food, or large plant saucers) but it's hard to find black or dark ones, most (here, anyway) are semi-clear, & your nocturnal BP would rather have a dark "cave". Use what you can both find, afford & cut a doorway into. At least for now- you can worry about being creative later.