I have just finished the development of a new Low whistle. It has a molded plastic mouthpiece which I cannibalized off of a low quality plastic instrument (not a whistle) and with some very substantial tweaking of the mouthpiece I can get em to play very nicely. So I put it on a PVC body and here’s the final outcome:

the Emerald Low D at a very reasonable $69.99 with free US shipping, $89.99 anywhere else in the world.
The parts are not expensive for me so that’s why I can sell it this cheap, but I’m VERY happy with the sound!
Here’s a link to a youtube video so you can hear how good it sounds!
http://www.youtube.com/watch?v=z7QrQ6mMcRg