your beautifull hourglass is also shown in "The Art of the Paperweight - St. Louis" by GĂ©rard Ingold.
In total 300 pieces where made, from which 150 where reserved for distribution in the USA.
Some weeks ago, I was in the Baccarat & St. Louis area and visited also the Centre dÂ´Art Verrier (ciav) in Meisenthal. There is a hourglass like yours on display. I was told it is worth something between 1.500 and 2.000 $ depends on his condition.
Hope this helps you a little