Hey Kid,Original Wheels are the way to go. Your wheel does look pretty bad but I'm sure you'll be able to find a replacement or find someone to fix it if possible. You'll have a blast driving her once the restoration is over, I know I did when I first drove mine after it was finished.
I agree that the Lotus Brand wheels are one of the best looking alloy wheels there is, but I still think 13" tires are hard to get and won't get any easier. They will always be made but they will just be more of a pain to get (now, if someone would just make a 15" version!). Actually, I don't think it will be too long before even 15" tires will be harder to find, but I think that will be a few years away.
Enjoy them while you have them! They look great on the car!