Details, details... :-)
But yes, thanks for the advice. I'm making these for a friend, and she's paying for materials, so naturally, I want to keep the costs down. Buying a lifetime supply of thread on her dime isn't in the cards. Campbell Bosworth does carry the # 10 thread, but I believe a local art store here carries it as well for bookbinding uses.
I've read your blog extensively and am quite jealous of your talents. I'm also jealous of the fact that you live in Auckland. I lived in NZ for most of a year in 1988-89, and I loved Auckland. I'd go back in a second. (You just can't get Speight's or Double Brown here. We have our own good beer, but it's not the same..)