Serendipitously, I just sent in two WM sleeping bags that I've used quite a lot in recent years for the same thing: restuff, overfill. The price you list is a bit lower than I was fearing, so hopefully this will work well for me too. I'm not sure yet how much overfill to go for (one is a summerlite, the other an ultralite); hopefully they'll be able to recommend something when they call.
Overall the bags were in pretty good shape after so much use, but even after washing, drying, and maximally fluffing them up, holding either one up to a strong light source and feeling around I could still find areas now with little or no down --- those one or two feathers seemingly lost per night really add up!
When I called, WM did warn me that in the holiday season they're pretty busy, so I shouldn't expect quick turn-around.