If you are looking for death or birth records, you will have to get those yourself, counties/states require proof of who is asking for the data.
I think you may have some misinformation, Isanti is a county, but Stacy is a small community in Chisago County. There is no township of Stacy in Isanti county. County seat for Isanti is Cambridge & Chisago City is the county seat for Chisago county.
Couple of questions: Have you checked the archives for the newspapers, such as the St. Paul Pioneer Press? There are small weekly newspapers for both counties, have you contacted them for info?
Do you have her death certificate? Many times it will list the funeral home or church, you can then contact them for information.
Have you contacted the Isanti County historical society or the MN state historical society about what records they may have?
I think you need to start with her death certificate, find out where she died, where she is buried and then you might be able to find an obituary. Remember not everyone had an obit published.
Geneology requires a lot of time spent in court houses, historical societies, libraries, etc., reading/searching old files, many times finding nothing. Not all records are on line, especially the older ones.
Good luck on your search, if you have other questions, let me know. I lived near Stacy for many years, so I may be able to offer suggestions of where you can search.