If I remember correctly, Iaijutsu focus doesn't require a katana at all. I think there's at least one build out there that uses daggers and Master Thrower's palm throw.
It doesn't, but I did it cause the Iaijutsu master gets finesse with em. I know, very minor damage boost overall but I kept it for flavor.
Been there, fought that, died horribly.
Something fun and flavorful to get your DM throwing books at you: Katana Chucker