What would you want? Where are they actually used?

• Straight Halbach Array
  Our neodymium magnets have the hole parallel to the magnetization direction. The north and south poles are on faces where there is a hole.
• Check out a common refrigerator magnet
  The most commonly seen example of a Halbach array is the flexible refrigerator magnet. These thin, flexible magnets are often printed on for use as refrigerator magnets or on the backs of cars. They are much weaker than a neodymium magnet (only 2-3% of the strength). Stanford Magnets can offer refrigerator magnet for your requirements.
• sticking to a steel surface
  If sticking to a steel surface is your goal, there is an even better option: the Mounting Magnet. Mounting magnets use a steel channel or cup to redirect the magnetic field from the backside of a single magnet, which roughly doubles the pull strength you might expect from the magnet alone.
• Halbach Cylinders and Rings
  Halbach arrays can also be configured in other shapes. A ring magnet with multi-pole magnetization, or a ring made up of smaller arc segments can be used in this way. Different magnet configurations will yield different directions and strengths of the magnetic field within the hole. We can also offer Arc Segment magnets