Try doing a search at www.uscamgrounds.info and you'll see four in the area which no doubt are cheaper than what you've found to date if cost is the factor. Good luck.
Try Babler State Park.. Its not super close to Earth City, but its in a nice spot, in the distant suburbs of St Louis. http://www.mostateparks.com/babler/camp.htm
I think you can head north from there and get into Earth City.
They have Elec & Water sites, not sure about sewer..
There is a spot in St. Charles which is on the other side of the bridge from Earth City. I cant rember the name of it but it is close to the river on the north side of St. Charles city. If I remeber rite you take the 5th street exit off of highway 70 and follow it to the other side of town. Bill Thomas camper sales also has spots to camp but your on blacktop with nothing to look at.
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There is a campground at the Casino Queen in East St. Louis, Il. which is about 20 miles from Earth City. Bill Thomas Rv in Wentzville will let you stay there if you are needing service or have bought your Airstream there. They do not have water at the present time though. You might look on the website of campgroundreviews.com.
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