Sorry, no could find although Electrum claims to be in an open access journal but only very recent material uploaded. Could be worth a shot contacting the editors direct - http://www.electrummagazine.com/
I think the journal Electrum is a relatively modern one, but the one I'm after is a chapter in what I now know to be a book called 'Roman Military Studies , edited by E. Dabrowa (Krakow: 2001). The series the book is a part of is also named Electrum.