Any ideas as to what kind of Brodie/Tommy helmet this is? Rivet placement and liner are completely different from anything I’ve seen. Seems to lack the manganese rim around the helmet, could be a Mk. I shell but seller claims that there are no visible stamps. Some groups on facebook have said it might be a Dutch M16 variant, Greek produced, or a British Mk. II Civil Defence helmet, but I cannot find anything on the interwebs that supports either point.

Any ideas as to what this is and where it is from?

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