That's the way I saw it when I reworked the nav lights on my NS27. Tricolor at the masthead with anchor light underneath. Steaming lights still at deck level, with stern light on the pushpit upper rail.
It's my understanding that if you have a masthead tri-color, you cannot use a stern light on the pushpit. Anyone who knows for certain that this is not so, please feel free to jump in and set me straight. To the OP, in your case, a masthead tricolor and anchor light would work well. LED bulbs or fixtures will save a ton of electricity though cost more up front.