Sure, I can do that! If you have access to labware, like 1L beakers, etc, I could put mine in those.
I skipped the whole repackaging thing. I did end up making a little blizzard with the shopvac on accident (ended up returning it), and ended up just have studying my quilt which worked out fine. Clean up was pretty easy since I did it in my cleaned bathroom.
When I made my down hood, I had the down bag in the bathtub and used my vacuum with mesh on it. It worked perfectly and I didn't make any mess since my vacuum can only suck. What little down that did manage to escape from the bad was contained in the bathtub, which I vacuumed up and put back in the bag.
It would be kind of hard for us to tell since the fill power is based on laboratory conditions. Also, the US testing does some stuff to the down first to optimize/maximize the fill prior to testing, whereas European down does not "artificially" inflate their numbers like that. Which is why you'll often see people say 800FP EU down = 850FP us, or sobering like that.
Also, I believe they put a standard weight down on top of the down to account for any excess air gaps, etc, then measure how much of the graduated cylinder/beaker the down fills.