Its always better to see the physical stone when buying a diamond.
Same like buying a Rolex, would you buy one online even if its a few hundred cheaper ?
Go to a physical store ask for stones in your price range, if you don't like it say thanks and walk away.
Singapore has more than 10-20 good stores to buy diamonds from, you can go to a big mall go in tell them what you want (eg, price, specs, settings, etc.) take their name card and give them your number.
Within the week they will call u and tell u what they found, decide which fits u better and go to the store to see. Likely you will get to see 10-20 stones of the range u require.
From there take some time (if you are not in a rush) and pick the best one you prefer. Btw diamonds have huge mark ups so you can actually haggle the price down further by 5-10% more.
