Swift Chamonix Roof light Replacement

[DaveB]

I have a Swift Chamonix which has a roof light. The double glazed unit has blown, and I m having difficulties getting it replaced. Can anyone help please?

 

[Damian]

Not enough information to provide any possible solutions.
Where is it located ? what size is it?
A photo would be most helpful.

 

[Beachball]

What year is the Swift Chamonix and like what someone says a photo would help