If history is any indication, Nebraska would own Sparty. Nebraska has played Michigan State five times and won all five. The first game was in 1914, a 24-0 win. Then in 1920 it was 35-7 Huskers. Then Sparty had the misfortune of playing us in '95 and '96, which resulted in 50-10 and 55-14 wins, respectively. The last game between the two was the 2003 Alamo Bowl which Nebraska won 17-3. Must have been something wrong with the offense that day.
The Spartans have three Big 10 trophies they play for - The Paul Bunyan Trophy in the rivalry against Michigan, the Old Brass Spitoon against Indiana, and the Land Grant Trophy against Penn State. The Land Grant Trophy was started when Penn State joined the Big 10, so it's probably proper that some type of trophy be established for a potential Nebraska - Michigan State match up.
You're welcome to suggest your own trophy in the comments section.
If there is one thing that has salvaged Michigan State athletics, it's their basketball program. Tom Izzo has taken the Spartans to six Final Four's, winning the 2000 National Championship. Sounds kind of like the Kansas of the rust belt.