Wally and Wenda (or Wilma!)
What's great about this costume is there can never be too many Wallys and Wendas/Wilmas. The more the merrier!
What you need to do: Get a red- and white-striped shirt, red and white cap, black- and round-rimmed glasses, and a pair of jeans. Wenda's glasses are a little more triangular, and she also wears red- and white-striped socks, along with a denim skirt.