I would try sifting it. H-380 is a very uniform round ball powder. 3031 is a good sized tubular extruded powder. Seems of all of the powders to be mixed, these two would be the easiest to sift. You could do it in small amounts over a plastic tray to see there are no pieces of the 3031 getting through.
With powder prices right now, I'd give it a try. If it doesn't work, toss it.