Jess Epple, Jr., edited the book and furnished new illustrations, then had the volume privately printed (just as the orginal was privately printed). Although this is sold both at OHS and here at Honey Springs it was NOT published by the Oklahoma Historical Society. [Jess Junior also donates a major portion of the proceeds to Honey Springs!]
Jess Epple, Sr., interviewed participants in the battle during his youth and was a member of the original Honey Springs Battlefield Centennial Commission in the 1960s.
(If I remember Jess Jr. correctly, Jess Senior's widow burned quite a bit of his original research when "cleaning house" in the years following his death.)
For general interest in the era, I consider Whit Edward's "The Prairie Was On Fire: Eyewitness Accounts of the Indian Territory in the Civil War" to be a great resource.