“If you’ve ever wanted an anniversary band, here’s the greatest suggestion ever.” The deep, honeyed voice belongs to Dallas Prince, a blond woman the TV camera captures seated at a desk before zooming in on her design: The Reversible Eternity Ring is rotating to showcase every detail-covered angle.  “Get two of these and jacket your solitaire with them,” Prince explains, slowly and thoughtfully laying out her pitch. “So one day you have blue diamonds as your jacket, and the next day you have champagne diamonds as your jacket.” The pitch works. The ring—14k gold lined with nearly 2 cts. t.w. diamonds and appraised at more than $3,500, according to the Home Shopping Network—sells out in minutes, at a price of $1,399 (or four flexible payments of $349.75).  This is one of countless appearances Dallas Prince has made on HSN and EVINE Live (formerly Shop