Just like the title says. I am curious.
Not all keys are available from all makers, but you can get whistles in keys ranging from soprano G to bass G and everything in between.
Anything smaller than soprano G would be extremely small and high pitched, and most people can’t manage bass whistles because the average hand size is too small for such large whistles.
In fact, many of us can barely handle tenor D whistles… but most of us can eventually manage them after enough practice and conditioning.
Apparently, from what I gather here http://chiffboard.mati.ca/viewtopic.php?t=17285
the quoted whistle comes in a quite different key…