Thanks Ron
I also think that it is so. But When I found this one I try to find result any way.
["short_sword", "Short Sword",
[("sword_norman",0),("sword_norman_scabbard", ixmesh_carry),("sword_norman_rusty",imodbit_rusty),("sword_norman_rusty_scabbard", ixmesh_carry|imodbit_rusty)],
itp_type_one_handed_wpn|itp_primary, itc_longsword|itcf_carry_sword_left_hip|itcf_show_holster_when_drawn, 183 , weight(1.25)|difficulty(0)|spd_rtng(103) | weapon_length(75)|swing_damage(37 , cut) | thrust_damage(35 , cut),imodbits_sword ],
It is in native 903.
Both sword_norman and sword_norman_rusty are multimeshed.
sword_norman ; weapons1
sword_norman.2 ; steel_medium
But as it seems, this weapon is not used by any troops, so it must be as you said.

I will try to find single material solution.
