[morzh]

As I said, I use 1W across the board, as this lets me not having to think about what wattage I need and where, short of, of course, the wire-wound dividers.
Also 1W axials ares also more convenient, having thicker leads. Even though none of them as thick as the original resistors' ones.

This said, anything above 200K does not need to be 1W (even if you have a dropout of 200V across it, the dissipation would be 0.2W), and so if you have the needed value of 1/2W rating, this will do just fine. But if you don't, buy 1W resistors.

In radios that use larger resistors divider (like that 13K-15K-10K-10K one ins a 16) where the 1st resistor, like the 13K, is pretty big (looks like a 2W) I use 3-5W size.