Amazon has the 16oz Amazon Brand Happy Belly Dressing (Creamy Caesar or Traditional Italian) for $1.76 with free shipping on $25+ or with Prime (extra 5% off with 5+ items S&S order). Other 16oz options under $2:

• Balsamic Vinaigrette for $1.81
• Zesty Italian for $1.80
• Blue Cheese for $1.80