You can search for those issues on ebay. Now that I know the issues I can ask others who may know.

I have the Feb '71 and Sept '70 issues. The Feb '71 has nothing like what you describe. The Sept '70 does have something similar. It matches your description except she does not have any heavy eye makeup (only mascara) and I do not see any brown or sepia tone on the page. It's a full page portrait on the left side of the page with a narrow section of text on the right. She is wearing a black and brown crocheted hat and a huge, black crocheted scarf. That is all that is visible in the portrait. She has long, straight, dark brown hair and is looking at the camera (straight ahead). She's the only one on that page. There are two other pages next to her's (part of the same fashion article) that also have large, full page portraits, but they don't match your description at all.