Hey there & welcome to Tnet.To me it does not look strong enough & seems small for that.But that's all I can say.I've looked them up & see none that small & thin looking.To me it resembles a clog clasp from the 18th - 19th century.Maybe some of the Brits. will chime in on a thought.5th century over here is out of my league.Hi friend. Another person, he told me, that could be a piece of Visigoth belt buckle. Is it possible?
Thank you!