If that's all you need to do you might be able to get away with white rouge only. If not, tripoli followed by white rouge will do the trick. That way might be easier as tripoli is a more coarse compound and will work on the water spots and dullness more quickly.
You can get either/both at Sears or online at places such as eastwoodco.om or wttool.com or caswellplating.com. Tons of others as well, but those are the places I know off hand.
For tripoli, use a ventilated flap wheel. For white rouge, a loose sewn wheel that is just held together in the center near the shank hole and kinda 'flops' around.