Pakex are a small distribution company, mainly dealing in packaging and janitorial supplies - their registered office is an accountants' office in St. Albans, and their
distribution centre in Welwyn is a small warehouse. The other approved suppliers of BR1B keys (DJM, Unipart Rail/Railpart and CrewKit) had their keys
made in the UK. Pakex presumably decided to outsource the manufacture of their keys to China to cut costs (VeryCharms are seling a pack of 5 for £3.45, HOPS sell one for £7, so how much are Pakex making on them?), which has exposed them to the usual 'one for you, two for us' issue that comes with outsourcing to China and means these keys are now everywhere, being sold for buttons.
The items being sold on Etsy in the OP are from a US company called
VeryCharms based in Louisville, who sell cast metal jewellery supplies (presumably sourced from China). There is another seller on Etsy in Florida sellng them as
shower curtain hooks. The ones sold on ebay/Amazon/Aliexpress etc. are coming direct from Chinese sellers in Shenzhen and Shanghai.
All the BR1B keys I can find pictures from other approved suppliers are chromed steel. The Pakex ones (and the ones sold by HOPS, who presumably are sourcing theirs from Pakex) appear to be made from cast brass or 'bronze' - in fact, from the very visible seams around the edges it would not surprise me if the manufacturer recast a key Pakex had obtained from another supplier (the oval shape of the bow and the 'BR1B' engraving look identical to
this style of DJM-supplied key).