[Rick Becker]

Here's one place that advertises a soft window frame kit. (scroll toward bottom of page) I do not have any direct experience with them:

Porsche 911 2.0L - 2.4L Targa Upholstery, Seats, Carpets, Interior Panels, Convertible Tops, Floor Mats, Headliners and Other Trim Accessories from World Upholstery and Trim