I believe you heard about the Missouri State Guard account book when you visited us at the Missouri State Museum many years ago. The account book and Price's general order book are on exhibit there. Some years back they were photocopied by the Missouri State Archives. I noticed recently that they have been published by James McGhee under the title "General Price's Letter and Order Book, 1861; Missouri State Guard." I believe Camp Pope Bookshop has them. Good luck.
Bill Fannin, Curator of Exhibits, Missouri State Museum (retired)