Did you know that you can request photo reprints from the Pioneer Press? There is a link on TwinCities.com which takes you to an online form you can fill out with the date, edition, photographer's name and a description of the photo. This is submitted along with your contact info and the staff at the Pioneer Press will then check to see if that particular photo is available.
Not all photos will be: "Bear in mind that we do not own the copyright to everything that appears in the newspaper, and thus not all photographs are available for reprinting." However, if they find a photo matching your description, they will send you a thumbnail image for confirmation and you can then place an order.
These photos do not come cheap, but for those patrons doing ancestry research this may be an acceptable expense.
You can find the order form and pricing information here.