Seeing as this picture was taken like a millennium ago, the necklace is sold out everywhere BUT you can buy the chain and padlock separate!
Here is the lock at a 9, the rhinestones are set (as far as I can see) identically.
Here is the chain, also a 9. This chain comes with a lock on it already but they only have gold in stock.
Cheeky bonus: 5 plain leather wrist cuffs about the same size as his shown available here for less than £4. 8 (I don’t know what his clasp is like)