Phone Norman Clark in Rugby.
He sells a flashguard that fits inside the EB scopes front end. It does not need a cover to hold it. It simply pushes inside the tube and has a rubbery outside which grips the tube threads.
I have them on both my 10X and 20X.He also has extender tubes to fit at a very reasonable £4 odd.
However, I do use a cover with them to protect them when not in use. I would think they would be almost impossible to clean or repair if damaged.
Taz