Since there has been and continues to be logging throughout the UP, forest roads are abundant and criss cross vast sections of CFR lands. IF you stay on these and resist the temptation to charge off trail and snap off the young sprouts that take over after logging, you will do little damage and it is fun. However, I would not even think of doing this without a good GPS unless you know the lay of the land from many past outings because you can get well away from fueling points and therefore have a nice long walk out of some of these areas.
You can get a decent GPS for far below the $300 you mentioned above. Get one and learn how to use it...or stay on the trails til you do. Last thing locals want to do is head out to find a lost sledder.