Steve Carell and Toni Collette are set to start shooting “The Way Way Back” in Wareham and Marshfield, but they can’t do it alone. There’s an open casting scheduled for Sunday at the Boston Teachers Union Hall in Dorchester, but you have to be a member of the SAG-AFTRA union. Not to worry, we’re told there will be a casting call soon that is open to everyone. The movie follows a teenage boy who forges a friendship over the course of a summer that helps him to reconnect with his mother and stand up to his alcoholic stepfather. Filming here will be a homecoming of sorts for Carell, who’s a Marshfield native. ... Meanwhile, Boston Casting is looking for people with vintage cars from the ‘70s and ‘80s for use in Jason Reitman’s “Labor Day.” Interested? Send pics of your car to BostonPeriodCars@Gmail.com.