How many cups of flour are there in a pound?
The weight of flour varies immensely depending on how densely it's packed and the humidity.  If you've started with a weight-based recipe, I'd try to find a scale.

If that's absolutely not an option, I tend to approximate 100g = 1 cup.  

Be warned, I've found some recipes that are really sensitive to the amount of flour and the difference between a lightly sifted cup and a scooped cup can really throw off the results.  You might do better to try to divide another kg package of flour evenly and use the approximation that 0.6 lb is about 0.25 kg (i.e. one quarter of the bag).