Whether it is suitable for your MD player depends on the size of the unit you have. I recently purchased the Sony MZ-NH1 - not only is it easy to fit in the main pouch but you can also fit the remote inside the side pocket and, there is still space in the main pouch for a spare Hi-MD disc. There is also room for ear plugs if you so wish.
It doesn't have a belt clip (although I guess it is easy to buy a strong crocodile type clip if you so wish) and the belt loop is fairly large - it could probably fit around a small childs arm!