The microfilms have been claimed.
If you missed the boat and would like to acquire a set, however, you can order them from the Missouri Secretary of State's office.
Here is the link to the holdings for Clark County: http://www.sos.mo.gov/archives/resources/county/clark.pdf
Here is a link to the order form: http://www.sos.mo.gov/forms/archives/arch1.pdf
Each reel is $15, which is an absolute bargain (a lot of states charge between $50 and $80 per reel). Of course, if you live near Jeff City, you can access them for free on-site.