If you want a made in the UK magnetic copper bracelet a quick search on the net for made in the UK or made in England magnetic bracelets will find you some. These are some of the suppliers I found:
Laurence Butler Ltd. – http://www.copper-bracelets.com – all made in Cornwall, England.
Astral Magnetic – http://www.astralmagnetic.co.uk – at least some made in England.
Lilac and Cream – http://www.lilacandcream.co.uk – at least some made in England products – under the jewellery category I found some Laurence Butler magnetic bracelets and other Cornish jewellery.
As well as some on Amazon and eBay. There may well be other UK manufacturers of magnetic bracelets.