Tony Dixon polymer tunable low D whistle/flute duo. Comes with both whistle and flute head joints. Excellent players. Very easy second octave. $70
Click here for picture. The 4th one down. It looks sort of blue-ish but it’s really all black. This one doesn’t have the gold ring sticker things around each end. I removed them because I didn’t like their look.
Click here for sound clip. Never mind the mistakes and crappy recording equipment. 
~Tiff