How long has the black box been around in the short story "The Lottery"?
The black box has been around long before people have any reliable recollection. According to the story, some people suggested building a new box. Presumably the box was in poor condition. However, no one really does anything about it, because they do not want to tamper with tradition. This sentiment is what makes the people of the village have the lottery year after year.
This sentiment of changing nothing is so strong that the people say that the black box was made with parts of the original box. Hence, if we believe this story, then the box, at least parts of it, was around from the beginning of the village and the lottery. Here is what the text says:
There was a story that the present box had been made with some pieces of the box that had preceded it, the one that had been constructed when the first people settled down to make a village here.