At a recent militaria fair which I attended I got chatting to a dealer from the Irish Republic who had some ex Irish Army Stahlhelm type helmets for sale dating from the 1920s. He went onto tell me that although they looked like WW1 German helmets they were in fact actually made by Vickers Ltd in the U.K. during the 1920s. He added that the newly established Irish Army of the 1920s didn't wish to wear "British style" helmets and so this alternative was chosen. Perhaps Vickers acquired the tooling from Germany as part of the war reparations???