For a circular neodymium iron boron magnet with a diameter of 15mm and a thickness of 5mm, it is unlikely to reach 5000 Gauss, let alone other materials....
The 5000 Gauss magnet can only be satisfied by the neodymium magnet material. The size of the attractive force depends on the size of the magnet. The larger the size of the magnet, the stronger the magnetic force. In general, this field strength is easier to achieve with N50 and N52 grades, but only if the diameter is not too large and the thickness is not too thin....