are you sure about unclaimed property? I looked up your grandmother’s name and found it listed. It was listed under the last name only and Scout Energy Management was shown to have submitted it.
Each section has 640 acres. But, your grandmother didn’t own all the section. The easiest way to figure out how much net acreage is to wait to see what the nri is on the check. That is an eight digit number such as .00392704. you take that number, multiply by 8 (probably) and multiply that by 640 and that will give you the amount of net acres.