THESE ARE VERY RARE. The style is called “Regina,” designed in 1929 by Gerard Muller for his (exclusive) shop in Amsterdam. They were made for him at Josephinehutte in Germany. The flutes are 10″ tall. See the flutes in the painting by Pieter Claesz (Dutch, 1597/1598-1660). The price includes 5 perfect flutes at $230 each and one damaged at $85. The damaged flute has a clean break that can no doubt be glued using the proper product.
Gerard Muller (Amsterdam,1877- 1943).
He was a glass artist/designer and the Muller family owned a famous store selling vases and dinnerware. The store was located in the centre of Amsterdam near Damsquare ( address at Rokin, the company was named Glass house G.& A.Muller ).
Here is a PDF with lots of great info on Muller. Gerard Muller