Ok, thank you everyone - this is *probably* my last question. In light of all of the information shared, my financial limitations, and my interest in learning the fingerings before anything else, I'm going to go for a high D whistle. This might be a dumb source of influence, but... I see generation whistles in the hands of lots of the guys in my husband's Clancy Brothers themed YouTube play list (he's Irish, I'm Norwegian), so I looked hard at those. I am theoretically sold on the Jerry Freeman "tweaked" mellow dog in D. It comes as a set with a spare C tube in his E-bay store. It's a trivial additional cost for the spare tube, so my novice notion would be to just go for it. So, unless someone tells me in the next couple of hours "Don't, that's dumb, just get the D because______", I'll probably hit "check out" on this.
Thank you all for your patient, and clear replies
https://www.ebay.com/itm/Freeman-Whistl ... 27072#rwid