Deb, this 1976 Raleigh catalogue shows a mix of mixtes and regular step-through frames. It looks like the Super Course Mk II, the Grand Prix, and the Record all came in mixte models, and the Sprite, the Superbe, the Tourist, the Sport, and the Limited all came with regular step-through frames. (The higher end road bikes didn't come in women's models at all.) The 1977 catalogue is similar except that year the women's Sprite was a mixte.

I am really curious to know why they went with the regular step-through, since those frames are not as strong as a mixte frame. Was it cost or styling? I know a lot of people think mixtes are hideous.

Although that site is US catalogues, it might help you to nail down the age of your raleigh based on the components.