I make these basic rollers from plastic drain pipe. Good for working on long thin muscles such as on the legs. They are hard, so most people should pad them with a blanket or pillow.
I have stocks of some self-massage tools that I can sell you after a class or massage. Please read my self-massage advice before use.
Different shapes and sizes work for different parts of the body. Depending on sensitivity, you will need a different hardness. You can easily pad a hard tool to make it softer using a blanket or pillow, but the opposite doesn't really work.