Thank you very much Bob!!Welcome to the forum from New York. It is called .284 Winchester because it was designed by Winchester, but in the past there have been other manufacturers that have made it. Same as calibers like .308 Winchester, where the Winchester name has been removed for most discussions. Not sure if NORMA is making it any more, but you could Google it.
Best would be to make sure you get a supply of brass and a set of reloading dies unless you are going to rechamber the rifle, most easily with a new barrel.