I'm glad she's got some mobility. It could be that once you get her splinted, she'll get along even better than you expect. The good news is she injured herself in a very easy to treat spot, so the wrap will just be around her shank and need not involve the actual foot (wrapping chicken feet is ... a pain in the …)
Whatever you use on each side of her shank/leg- popsicle sticks, emery boards, heck: cinnamon sticks

-- the main thing is to ensure the ends of it don't rub either her foot or the joint above, so they'll want to be as long as possible to go the length of the bone, while avoiding rubbing joints above or below.
What I like to do is wrap the supports (popsicle sticks, whatever) in vetwrap (coflex, whatever brand of self-adhesive stuff) - they'll stay in place better when you go to splint. It won't take much - and then you can kind of pad the sharp ends at the top and bottom with the vetwrap. The vetwrapped support sticks will stay in place very nicely against the cotton pads and/or gauze so you can do the overwrap.
If she's overly feisty about getting splinted even with two people, consider wrapping her in a towel- a little chicken burrito.
p.s. love your truck, I've got an '88 F250 diesel, my favorite thing to drive … though the paint on mine … well … 'shop worn'