SheIn offers the SheIn Women's V-Neck Striped Hem Bodycon Dress in Red or White for $12.67. Coupon code "inst33" drops it to $11.95. (Uncheck the 99-cent shipping insurance box at checkout to see this price.) With free shipping, that's $6 off list and the lowest total price we could find. It's available in sizes M to XL.
It ships from mainland China and should arrive in three to four weeks.