I went with a background JPG I found called “old paper” which wasn’t parchment exactly, but gave the feel I was looking for, while representing a course paper rather than an animal skin parchment.
The photos were chosen to illustrate the text of the newsletter, and sized and worked in Photoshop. The text illustrations were made into duotone, but the newsletter logo header and a single background image, use for the character of the newsletter itself, not the article presented, worked better in CMYK, while keeping with the color scheme of the piece. The logo was constructed in Illustrator. All other work was done in Indesign. Right from the first read, it seemed to me that a table would be the best approach to present the comparative information in the article.