Inrush Current Limiter for microPC
They work on dc just fine and your reasoning about choosing the correct one is also sound. You probably know this but inside is basically a thermistor that has a negative temperature coefficient so when cold they will exhibit higher electrical resistance and reduce inrush current. They rapidly warm and the resistance drops.

You might also try inserting the equivalent to the warm resistance in series. This might be enough on it's own.

One caution; if you switch power off then restore it too quickly you may still get an inrush problem because the device hasn't cooled down sufficiently. There are mosfet circuits that do the same thing too.