Model trains use LEDs extensively now. Shops and suppliers of components have proved to be a wonderful source for LEDs and related products and devices for use in our field.
On this side of the Pond there are numerous choices. I would expect similar opportunities to find parts on original side of the Pond as well.

For a UK folk - https://www.componentshop.co.uk/

Nice to see they are on my side of the pond. 😊