The Collaborative International Dictionary of English v.0.48:

Unsight \Un*sight"\, a.
   Doing or done without sight; not seeing or examining.
   [Colloq.]
   [1913 Webster]

   Unsight unseen, a colloquial phrase, denoting unseeing
      unseen, or unseen repeated; as, to buy a thing unsight
      unseen, that is, without seeing it.
      [1913 Webster]

            For to subscribe, unsight, unseen,
            To a new church discipline.           --Hudibras.
      [1913 Webster]

            There was a great confluence of chapmen, that
            resorted from every part, with a design to purchase,
            which they were to do "unsight unseen." --Spectator.
      [1913 Webster]