The Forever Marilyn Blu-ray Collection for $25.99 shipped.  Here is a screenshot for your reference.  The 7-disc set features "Gentlemen Prefer Blondes", "How to Marry a Millionaire", "River of No Return", "There's No Business Like Show Business", "The Seven Year Itch", "Some Like it Hot", and "The Misfits".  Most places have it for about $67.