That's a good question. I would imagine that one of the restaurants nearby might accommodate you. There really wouldn't be a good place to do it otherwise, unless you had no wedding party, and you and your officiant stood on one of the stair landings. I'm going to assume they wouldn't restrict public access, so you would have to share with the others.
Heather is spot on in her thinking. I would ask at either the court house or the township building.
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