I talked to the GYCB guy at the Bassathon this year and asked him about that. He said that the Kinami and the Yamamoto baits are the same except for the swirl colors, someone else makes those. But as far as the grubs, flashes, worms, and palm trees go, they are all made by GYCB out of the same plastics with the same salt content.
I believe they are even made in the same building. Might check out getbitlures.com for some ika's. 6 pack for $4.00, custom colors available. Hand poured and a little better than the originals! Just cause it's GYBC doesn't mean its always the best bait, most expensive for sure though!