Wanted: princess to play Diana in CBS TV romance

The search is on for someone with regal visage and carriageto play the part of Britain's Princess of Wales in a CBS dramatization titled ''Charles and Diana: A Royal Romance.''

Shooting for the film will commence in England in May. Linda Yellen, producer of last year's controversial ''Playing for Time'' with Vanessa Redgrave, is producer of the TV film, which will air next season.

Monitor TV critic Arthur Unger reports that industry wags are already suggesting that Miss Redgrave be cast as the princess. CBS, however, is expected to play it safe and is anticipating a search for unknowns to play the title roles.