There are several small casinos right in the downtown shopping area of Philipsburg. They aren't flashy... in fact most people describe them as rather seedy. But if all you want to do is pull the arm a few times while your spouse and daughter hang out on Great Bay Beach or do other shopping in downtown Philipsburg, these should fill your need.
Take the water taxi from the ship's dock to the small dock at downtown Philipsburg ($5 for unlimited roundtrip passage all day through 6pm) and you'll find at least one casino within a minute!