Missouri is NOT a no-fault state. Missouri law requires all motor vehicle owners to carry auto insurance with liability limits of $25,000 per person for bodily injury, $50,000 for bodily injury per accident and $10,000 for property damage per accident. The MO law also requires uninsured motorist coverage of $25,000 for bodily injury per person and $50,000 for bodily injury per accident.
You can start here to get an auto insurance quote for the St. Louis area and see if MO is cheaper than your no-fault insurance in Michigan.
Comment Update: If another driver hits you and leaves the scene you should contact the police. They will investigate the hit and run and if they find the hit-and-run driver you can file a claim against them and/or their insurance carrier. If you carry physical damage coverage then your vehicle is covered. If you carry uninsured/underinsured motorist bodily injury coverage then your medical coverage would be covered. You should always purchase as much insurance as you can afford. The insurance will give you peace of mind that you (the victim) will be compensated.