Thanks for the posts Puppet Garage. This confirms the smaller sandcastle pieces, how the top of the jaw connects, and that the body and hands are still a mystery (and thought I would love to pump you for info on it, I figure you had to sign an NDA so I wont put you in an awkward situation).
Turns out that Smits is one of my wife's friends, who had her fanart retweeted by the cast over the weeknd. So to celebrate she came over last night with a shifter boot cover and larger sandcastle parts. So I have a bootcover filled with expanding foam and waiting for paint, that will work for her larger scale Waverly.
I tried the downspout Ron, it wasnt large enough. It is also usually rectangle, not square. I am going to keep searching for the correct part, Ill find it eventually. I still have hopes it is some sort of 6v flashlight casing (like Gypsy Eyes). Hopefully itll take less time than the Air Purifier for the desk console. Though after spending three weeks going through various toy and industrial websites, google thinks I am insane.
Smits and I are spitballed fleece and foam versions of Crow and Tom for conventions (ala Muppets) so Waverly may be on hold until that happens.