Cheapest way to do it will be via a Japanese import. If you use a proxy to order from one of the Japanese marketplaces (e.g. Yahoo Auctions, Rakuten) you can do pretty well.
For example, until midnight today (Japanese time) Rakuten Japan is offering 10% off all listings. So you can get a good condition used GS snowflake for about £2600 plus proxy fees (not much, certainly less than £100 including the shipping fee) and import duties once it lands in the UK:
https://item.rakuten.co.jp/dskatou/14292/
The biggest issue will probably be whether the bracelet is long enough to fit your wrist...