Without those it becomes a little more difficult. I always have used slate from HD or lowes, and just have them cut them. A long box that has only one open end, and is slightly wider than the male, and slightly taller than the dorsal fin stands on the male will be best. Just use silicone to put it together. These two stores will cut it for you for free, and the slate will cost $2-4 for a single piece which is enough for an entire cave.