The previous owner fixed the leaks by gluing them shut. While this was effective, I will need to repaint the roof in the near future and figured I'd fix the roofs at the same time. Do they look like they need completely replaced or could they be salvaged?

 

you might want to consider changing them out completly just because you probaly already have a problem with the rails or motor you will need to see what the problem is after removing the glue if it turns out you need rails theres sets on ebay

Land Rover Sunroof Rail Pair Guide Discovery I 1 and II 2 EGM100192 | eBay

 

Thanks for the link.