I could not find it among my favourite retailers like Gearbest etc, going anywhere close to Xiaomi advertised price. Everyone was double the price..
Then I found one on ebay for ~ £13 which arrived from Norway. (look for Item ID 192573959993)
Item arrived quickly and works great..All the instructions were in chinese, but seems simple enough to operate.
I like the minimalistic design & also appears to fast charge my Mi Mix 2s
Unfortunately it does not come with a charger, so I had to use my normal Xiaomi official fast charger, which came with the phone.