 and as low as $3.18 in Osage Beach and as high as $3.69 in Versailles for diesel. On the water, prices for 87 octane are as low as $3.69 to as high as $3.92, while 93 octane is as low as $4.49 to as high as $5.39. Diesel is coming in between $3.79 to $4.09 per gallon.