Some information on https://en.numista.com/catalogue/issuing_entity.php?id=2846
The International Currency Bureau Ltd was operating in the 1990's, based in London. This company has ceased to trade in and was closing in 1999. They produced patterns and experimental coins for various Central Banks and other currency issuing authorities. International Currency Bureau sought primarily to pursue contracts to mint and market legal tender commemorative coins, but failed to win major contracts. In pursuit of this goal, the company manufactured or commissioned the manufacture, many interesting prototype or pattern coins.
After it bankruptcy, an associate of the company was later also involved in the International Numismatic Agency, that mainly focused on fantasy coins.
Source: The Archive Collection of the International Currency Bureau Ltd. (https://archive.org/details/archivecollectio00glen/page/n9/mode/2up)