You can go to K-Rock by Ft Scott KS. Probably the closest. I was just at a local salvage yard yesterday and there is supposed to be a new park opening up close to Eureka Springs this month. Other than that there is SMORR. Wish I was closer to ya. If you ever come to Branson, let me know.
South of you is Roaring River and Mark Twain Nat Forest just south of Cassville. I will be there this comming weekend. My most favorite place in the world to camp and trout fish. It's not Colorado, but it's beautiful and has many sentimental memories. I have seen some "senic roads" off of 112 just south of the campgrounds, but have never driven them. I need to. You might try and contact Missouri Parks and see if they have any areas. I never thought till now to contact them. http://www.mostateparks.com/camping.htm