well...I think it is always nice having the chance to read again some good old stories.
Then, as a form of respect to the original author first I would contact him/her and ask his/her permission.
If he/she is no more a member here and/or cannot be contacted, I would not consider a breach of etiquette posting the story being careful to specify clearly who is the original author, so that the praises (and the critics
) go to him/her again.
To be honest I have found a couple of my stories posted on another web site, completely unknown to me and without my knowledge.
At first I felt annoyed, then I thought that they had been copied from the original site, a public site so actually I had nothing
to complain. I knew it was a public space. Then the user that had posted them, at least had put my nick as the author thus not
pretending to be the author. In that case I would have contacted the admin of the site asking to edit the post or cancel it.
..