Headliner

My headliner is damaged at the back of the roof and I don't think it's repairable, I've looked on the classic VW parts site but they don't list one. Are they available anywhere or will this need to be made? if that's the case can the material be obtained. I don't fancy the idea of using a second hand one as I tried this on a previous car and it never looked right.
 

The quick version is that you will need the backer board (originally fibre board, and a roll of headliner material.  A good heat resisting water proof glue spray and a weekend.   There are how to guides on this site

https://www.heritagepartscentre.com/uk/volkswagen/golf-mk1/interior/headliner-and-pillar-trim.html

Is it a tin top or cabriolet you have?

Tin top roof liners can be brought from here.

https://newtoncomm.co.uk/collections/vw-volkswagen-golf-mki

To fit them you need to remove some of the windows depending on if you have a 3 door or 5 door car, it's not a easy job to do so maybe worth talking to a specialist to price up the cost?

Yes it is a tin top and the kit sold by Newton Commercial looks just the job, all I need to do now is decide if I want to do the job or farm it out to a trimming company as I'm sure they will do a better job.