Hi Stuart and
I'm sorry I can't help out with parts but maybe a few suggestions. The bad news is that I'm not sure what car they were originally from. My guess is that the bracket is a Lotus only part, but the actual visor looks similar to the early Ford Cortina ones, which were apparently used on the 1960s Elan.
If you have the originals and the problem is the usual one of the internal foam collapsing, that seems a common problem and people have had them re-trimmed. Mine also need that treatment, but it's one of those jobs that it's easy to put off....
My best suggestion is to try Richard at Banks Engineering and see if he can help. They do fabricate a lot of parts so it wouldn't surprise me to find that he makes up visors for the Banks' Europa that they sell. If you've not used them before, don't rely on email from the website but give Richard a call, he is very helpful.
Brian