Keroro
Dororo: Ninja Frog
And riding a zebra.Is there really going to be a great deal of difference between the "correct" one and the "incorrect" one at civ scale?
I say give him an Ethiopian sword!
I agree that the difference between a Ninjato (whether historical or not) and a wakizashi would be minimal at civ-scale. I would imagine that the ninja is more likely to use a thrust than a swipe, so would recommend a stabbing anim. With a comparatively small sword I would also argue for a one handed grip - I would think that the ninja would want to keep the other hand free for a variety of other uses.
I think that a pair of the Sai that Hikaro posted would look very good at civ scale personally. Quite distinctive, and there are fewer doubts about whether they're authentic.