I think Rick's has complete decal kits for several of the stripes.
Original GM production methods for 1968-69 Camaros utilized the "doghouse" assembly style, which included the fenders, painted separately from the rest of the body. If the car was to receive the optional SS & RPO D90 sport striping, the factory also painted the fender stripes. After assembling the whole body, they applied self-adhesive vinyl on the doors to complete the sport striping. This vinyl decal set from Rick's, manufactured to original factory striping specifications, allows you to easily do the job with a self-adhesive, vinyl decal which duplicates the SS & RPO D90 sport striping on your car without the risk and expense associated with painting.