Question about unpublished but available manuscripts from authors

[Dustin]

I didn't see unpublished manuscripts in the librarian manual under either acceptable or unacceptable so I figured I'd ask what the policy is for a completed manuscript that was never published but is available to the public?
John Steinbeck (yes that one) wrote a werewolf mystery novel in 1930 under a pen name that was rejected for publication and the complete manuscript was included in his papers when they were donated to the Harry Ransom Center archives.

It looks like someone has digitized the manuscript and made it available on the Internet Archive. Would it be acceptable to request a it to be added to the site?

[Olga]

I would say no. I dug deeper (because it's John Steinbeck), it looks like this novel was never officially published in any way. Not as an e-book or on a more or less official website. I read that there are some ethical issues with this.
In fact this book is not available to the public. We really can’t say how much this digitized version corresponds to the real manuscript. Goodreads policy requires a trusted source for data. So for now this book cannot be added to the database.