The 1962 Chevrolet that is owned by the victim and her husband, that he drives her to the hospital for the birth of their child, has very modern (post 2010) 22 inch Billet aluminum wheels. Very incorrect for a movie set in the 60's.
(at around 6 mins) The ubiquitous red plastic cup seen in the bar at the movie theatre was introduced in 1970 (this segment of the movie takes place in 1963).
A cinema marquise displays "The Birds" as a film showing at a theatre somewhere early or mid-March as the plot takes place. That film got released on late March 1963.