If you were arrested the following applies:
Since it is valued under $500, and isn't an otherwise prohibited item (such as a firearm), then it would be considered a Class A Misdemeanor.
A misdemeanor stealing charge can carry a penalty of a fine of up to $1000 and/or up to 1 year in jail.
From Missouri statutes you would also be liable for a civil fine.
From Missouri statutes you would also be liable for a civil fine.
§570.087. 1.
2. An adult or a minor who takes possession of any merchandise from any mercantile establishment without the consent of the owner, without paying the purchase price and with the intention of converting such merchandise to his own use, or the use of another, or who purchases merchandise after altering the price indicia of such merchandise, shall be civilly liable to the owner for actual damages plus a penalty payable to the owner of not less than one hundred dollars nor more than two hundred fifty dollars and all court costs and reasonable attorney fees.