RKM
The most important piece of the puzzle your asking about is what you state above, from Kokugyo..."Kujaku - underlying netting pattern developed from Gin Matsuba, over which is the 'kohaku pattern' ". There is an old, some think "beat to death" saying, that, koi begin and end with Kohaku. The reason for this statement is that "most" all koi are judged based on a patterning "like" a kohaku. This doesn't mean that every variety is bred to kohaku, just simply that the "pattern" for achieving a harmonious balance start with the hi pattern as a base. Other colors, such as Sumi are there to "complement" not to disrupt the "Kohaku" pattern. So, when you are looking to purchase a fish which has red on it, first look at the red only and see if the pattern is pleasing to your eye. Then, look at, say, the sumi, to see if it is balancing the look of the fish and the red pattern. If it does, then that's the fish you want to buy. Again, as stated above, buying fish for breeding purposes is a whole different ball game. You look strictly for the highest quality coloration and forget pattern. It is not important in parent fish.
Now on to your main question - If I were going to breed to get Kujaku, I think I would use a hariwake (either orange or red) as a female, and a Gin Matsuba or two as the males. You'll get better fertilization of the eggs if you use two males instead of one. Of note, there are actually 3 colors of Kujaku - Red, Orange and Yellow. Yellow being the rarest, but if you ever get the chance to see one of high quality in person, you'll understand why I personally feel they are the most beautiful of all the Kujaku variety.
Good Luck on your quest - would love to hear more after you get your parent stock. Take some photos and post them for all of us to see. Should be great fun.
Regards
Mike