Best Buy offers Chitty Chitty Bang Bang on Blu-ray / DVD Combo for $4.99 with free shipping. (Amazon charges the same for Prime members.) That's tied with our mention from two weeks ago as the lowest total price we've seen for this title. (It's a current price low by $9.) This 2-disc set includes the film on DVD and Blu-ray disc.
Update: Note that Amazon ships it in one to three weeks.