Vango Hex Hub UV damage

[California Dreamin]

We have an old but much loved Vango Hex Hub. Not the driveway style - just the original hex. It’s green on the sides and light green on the roof and I noticed that from the inside one can see damage right at the top near the apex. See photo. It’s not visible from the outside. I don’t think it’s leaking (yet). It’s looks like not only is the hex no longer available but the driveaway version is o my available in a rather depressing grey colour.

Does anyone have a green hex they no longer use?

Is repair an option do you think and if so then where? It’s not the whole surface - just the top few inches.