Just thought I'd show what I use to store/transport whistles.
I'm curious to see what others use. This is a drumstick bag I bought off fleaBay.
My favorite part is the Woodland Camo that makes me look like a whistle commando.
Outer compartment stores some whistle bodies and odds & ends.

Inside contains the full whistles with heads.

As for individual storage, thanks to a thread here at C&F, I was able to track down some of the square plastic tubes that Dixon uses.

I read a couple of complaints that the inner half of the tube would etch a line into a whistle over time.
So I headed off any future damage by affixing some sticky back foam around the lip of the inner half.

Let's see those whistle bags!