There are several manufacturers who can help you get good hardness testers. They are of different types i.e. Rockwell, Brinell or Vickers machines. You will need to specify more on what exactly that you are looking for and the application you have in hand.
Hardness is a characteristic of a material, not a fundamental physical property. It is defined as the resistance to indentation, and it is determined by measuring the permanent depth of the indentation.