Cheryl — The "blue book" gives that registration as by
International Bottle Co. Ltd. on 26 January 1928. I believe that they were factors, taking a requirement, designing it if necessary, putting it out to tender, and obtaining its manufacture. Most likely a British client, but it could have been made anywhere in Europe, including Britain.
Look for Continental 7s with the crossbar, a positive indicator of a mainland European mouldmaker.
Bernard C.
