I’m an adult with CF. I think it’s a great idea to find your son someone his age to connect with online. I’m sorry he’s feeling alone. I think everyone can agree that it helps tremendously to find someone with shared experiences when you’re going through tough times. I’ve contacted my local CF center in the past about helping to start up a buddy program of some sort for kids, but it never worked out. If you don’t hear back from someone on this forum, try contacting your local CFF chapter. They may be able to put you in touch with someone that has expressed an interest in something similar.
My clinic has a facebook page and recently posted information about an online site for people with CF of all ages to connect. It looks like there’s Skype, and games like Club Penguin, Mindcraft, and Roblox to play with other kids with CF. I think it's a new site, so I'm not sure if it has many users, but it’s worth a try.
Here’s the site:
Good Luck and I hope he finds a CF friend soon.