Parts for Mark 1 skylights

[Jannlloyd]

We have just bought a lovely mark 1 Tvan, and are busily tidying her up.  Can anyone give me the name of, or any information about the make of the early models skylights. We need the internal cover that fits onto the base of the skylight that covers up the part that protrudes directly from the fibreglass through into the bedroom.  The skylight itself is in good condition but the part I've mentioned is missing.  We want to sort it out before carpeting the ceiling.  Any information is most welcome.