Drawing has begun, but it will be a little while until I have a page finished enough to share. Until then, here are some of the photo references I have chosen to represent some of the more important objects in the story.
Here is Iowa’s skeleton key:
And the cowboy’s hat is a big Montana, as worn by the classical movie serial cowboy: 
(I adore the color combination on the felt, and the ribbon binding on the brim.)
I had no luck at all finding an image of a proper saddle for a large bird– apparently people who ride ostriches either improvise from horse equipment, and saddle seat/English equipment at that, or just ride bareback. So I am going to wing the saddle from the basic design of a Western saddle:
Of course, I have way more moa references cued up than I have room for here. But for maximum creep-out factor, here is an actual preserved moa foot:
Moab is not a creature to be messed with!
Wasn’t the saddle going to be based on a camel saddle?
It started out that way– a camel saddle was one of the story seeds, and I just sort of used it as a suggestion, since I had already taken two of the seed objects intact in the “correct” manner. The trouble came when I tried to fit the camel saddle onto the moa, and then put the cowboy in it. It just didn’t work. The whole thing just looked funnier in my head with the standard big ol’ cowboy saddle with all the leather flaps and straps.
We’ll just have to see if I can communicate that in the drawings!