https://www.barnwell.co.uk/bristol-branch-is-moving/
In a different life, many years ago, we used to use their Avonmouth depot for any unusual seals. They would make something if they didn't have it on the shelf.
Was part of the CES for Foden Wreckers. (Supposed to be) used by recce mechs when winching at night.
Search ebay for Bardic Lamp Battery Conversion Kit