One of mine is NMIB and the box says 9540 RESEARCH, which means it was sold for market research before they decided to sell the color in full swing. I'm afraid the color didn't become extremely popular among fishers at the time, as Heddon didn't bring out so many of 9540's in this color.
I am thinking this color may have derived from other manufacturers such Whopper Stopper, Bomber, or Fred Arbogast. You may find much more of similarly-designed lures like Hellbender, Crapshooter, or others.
I changed lines of my reels and am looking forward to going out for fishing with them, but we'll have a big typhoon soon. I'm hoping it will not bring tough times to Japan any more.