Tamiya releases a few of their model kits, built and painted... check with Tamiya's distributor in Singapore, or head to Tiong Bahru plaza's hobby store on the 5th floor - the owner is a warship fan... But most of the pre-built/painted warships are in 1/700 scale... and not super detailed to the max...
The game Axis & Allies: War at Sea has pre-painted miniatures of WW2 ships but they are 1/1800 scale. Details aren't that fantastic but servicable. What do you need them for?
I've seen their 1/700 waterline series up close, pretty basic right out of the box and neatly painted. The 1/700 series a lot more difficult to detail up due to the smaller scale... You'll need to squint your eyes (close the aperture that is.. :bsmilie when you build them..
I didn't pay much attention to their pre-built series, coz I'm mainly the do-it-yourself modeller.