Also just noticed that it way your thread on Joon and Tommy that had me sputtering coffee last night to the point that dh had to know what the heck I was reading about. You have a real knack for painting a story.
My BO is the one I could give puppies to, she's an awesome mom. Silkies are known for going broody and mothering almost anything too. They aren't as big as a BO, but if you're only interested in a couple of chicks at a time that could be a good option too.
ETA: I see one of your girls is an EE...
I've done it a couple of times and haven't had any problems. You want to let the hen be broody for a week or two before you give her chicks and it seems to work best if you do it in the evening when they are kinda sleepy. I have one hen that I could give her puppies in the middle of the day and...