Woodchuck is supposedly tough to skin, henc it's not always carried by the supply houses. A whole skin sounds like a treasure.
I think it was a chuck caddis that Len Wright talked about in Fishing the Dry Fly as a Living Insect. ( hope I got that title right w/o checking my bookshelves)
The mass of men lead lives of quiet desperation, unless they fly fish... with apologies to Thoreau