I am currently working on collecting some appropriate miniatures to show the flavor of the setting. If you want, I can convert some to represent your characters in particular. Otherwise, I’ll mostly just paint the samurai with axes and hammers to have black hair and blue-gray cloth (Crab) and the ones with swords and spears to have white hair and sky-blue cloth (Crane).
The Bushido miniatures game has some appropriate (if expensive) figures. For ratlings, I recommend the Skaven range from Games Workshop/Citadel Miniatures, of which I will have a few. But the one thing I’m having trouble finding is the wonderful but out-of-production Rackham Confrontation goblin ashigaru of No-Dan-Kar—preferably with the war staff (leader, biwa player, and standard bearer) for variety.