Buying a diamond ring

So I want to buy a diamond ring.

I’m not entirely sure on prices in Taiwan, but I’m guessing like most premium goods, it will overpriced.

I’ve found a ring I want online (UK website), worth about TW120,000 but how much customs duty will I have to pay on it?

Any info would be helpful, cheers.

I heard Hong Kong is the place to go and the savings on big ticket items would cover the trip.