Seven of these cards are available.  There are many other cards with very similar photos but these seven are all the same, from the early 1980s when the hotel was (obviously) still operating under the Hilton name.  Four are unused.  Of these four, two are Grade: 1 ($3) and two are Grade: 2 ($2.50).  Two others were mailed in 1982, each with multiple stamps, indistinct postmarks, and some postmark smudging on the fronts (Grades: 2, $4).  The last was mailed in 1980 with two stamps and modest corner bumping (Grade: 2, $4).