Parrish's works seem to be mostly in private collections along with a few scattered museums. For many of us, the most conveniently seen examples are murals in two bars. The west coast example is his Pied Piper mural at the Palace Hotel in San Francisco. The other is the King Cole mural in New York City's St. Regis Hotel. The locale is the King Cole Bar that I briefly visited last September.
The mural dates to 1906 and has been in the St. Regis since 1932. Happily, it was given a cleaning a few years ago, as this New York Times article mentions.
Here are some photos from our visit.