You don't "use up" the feathers through the quest, as you can retrieve them from the (sauna) stove if you've followed the instructions (I suspect they now burn, which they didn't earlier, but you should put them in after the fire has died down anyway).
The quest is not unique, so you can get it again at a later time.
I don't know if a paw hacked in would be functional (my current character has a number of them, and so doesn't really need to hack any in).
And, by the way, the feathers came from the bird, not the thief