I don't know if this will help at all, but a couple of weeks ago I was into Bass Pro shop in Tacoma, WA and they had a whole bunch of cases of 5.56 ammo out on the floor..some new manufacture, and some re-manufactured.. My estimate is that there were at least 75 cases of a thousand rounds of each kind out on the sale floor.
ETA: I know that OP asked about Eugene, Oregon, but if he strikes out everywhere else, perhaps Bass Pro would ship some to him.