Where to find these heater parts?

[georgeyv]

Hi all

After recently re fitting the engine I came to attach the heat exchangers to the pipes, it was then that I realised I was missing something. This is what came off one of them, it's now stored in a bag and I imagine it's likely to be asbestos so wonder what has been made to replace these parts?

Cheers

 

[Trikky2]

Heritage sell good alternative ones.