The Iron Age Pin Jewellery Range can be purchased direct from Ortak : https://www.ortak.co.uk/collections/the-cairns-pin-new-collection-2
Previously a bronze version was available via Shapeways, but sadly this venerable 3D printing service has gone bankrupt and as such there is currently no way to obtain this version. There are plans to cast the pin in bronze using the same methods discovered at The Cairns but these are not available currently.