I look to the registered address because the UK gov reduced the import duty threshold from 35 GBP to 15 GBP (to pay for ............. Agh!).

But curiously the next purchase is a Chinese company (address in Kata-Kana) in Lundun (innit?). The prices from China direct are the same. We will see, but other purchases in a similar vein did not incur import duty at my end. eg

shoes from Wish.com came direct from China despite their registered address in the UK. But then the declared value was about 1/4 of my cost and under the threshold.

FWIW the GF bought me a  watch  and Timpsons replace the battery for as long as I keep the ticket for a one-off price, but it ain't .............

Years ago I tried to buy a rechargeable AA battery with built-in USB connector. I heard nothing for a week so cancelled the order. The vendor had just started his "shop" and gone on holiday for 2 weeks!