Not sure of any good camping site in the NF, but here is my tracks from driving in the area.
Here is a Garmin GPS map showing open NF roads.
Here are the rules for camping in the NF.
Camping is allowed anywhere on National Forest land unless posted otherwise. A permit is not required to camp on National Forest land. Your campsite must remain at least 200' from water and approximately 150' from roads and trails. There is no camping within 1/4 mile of the Pere Marquette River on the Baldwin Ranger District and the Pine River on the Cadillac Ranger District, except at Peterson Bridge Campground or other designated campgrounds along these rivers. Camping is allowed for a period of 16 days in a 30-day period on National Forest lands within a ranger district. There is well water available at our campgrounds. If you are disperse camping, it is recommended to carry a water filter with you. Between the months of March and October/November, please be conscious of weather conditions such as strong wind and dryness in the forest if you plan to have a campfire. Campfires are permitted for cooking and warming even during high fire danger times. Be sure your campfire is dead out with water before leaving your campsite