I'm not sure why Grado would say that. It looks like it has a standard 1/2" mount. They may have been thinking of a different turntable. Check your current cartridge. Measure the distance between the mounting holes. Should be 1/2". If so you can use just about any modern cartridge.
The Grado Prestige Blue would fit the bill perfectly and allow you to upgrade the stylus in the future.
The Grado Prestige Blue would fit the bill perfectly and allow you to upgrade the stylus in the future.