I am sure there is an actual name for the style, but I do not know what it would be. However, use keywords like "50s nostalgia clothing" when searcing online. There is a great website called rustyzipper that sells vintage clothing, shoes, and accesories from the 20s to the 90s.
since I haven't seen the Stepford wives. Im gonna guess your looking for a June Cleaver type dress. If this is the case your best bet will be to make it yourself if you sew. Not sure what they dresses are called. but the skirt is a circle skirt. Very simple and easy to do.