Over a year ago, I got a deal on some 750fp down, and I bought 9 oz of it. I'm not sure why I didn't get more to make a top quilt (I'm currently using a sleeping bag). Now I don't know what to do with it.

Buy more down? 750fp doesn't seem as readily available any longer.
Just buy 800 and use a mix?
Just buy 800 and use 750 in some baffles and 800 in the others?
Is 9 oz of 750 enough for a 3/4 3-season underquilt?
Should I make something else?

What are your thoughts?