There is a watch store in Woodlands Centre selling the 25th Anni jelly Frogman for $510. I believe they only have one in stock. Location is directly opposite KFC. Take note Woodlands Centre is at the Woodlands customs.
They also have the jelly DW-6900 from the same series for $170 and the Eric Haze DW-5600 but I am unsure of the price.
I don't know whether $510 for the Frogman is cheap or not so don't ask me if it is a good deal.
Another kind member has informed me there is the same jelly Frogman selling in Hardwarezone forums for $480.
Just to let all the Frogman fans know. Personally I won't pay so much for a G-Shock unless I run into alot of cash.
TAKE NOTE: ALL PRICES ABOVE ARE IN SINGAPORE DOLLAR.