IIRC anything Lv50 and above should have RDM and SAM weapons. I know I've personally seen a moogle fencing sword, and a Titan katana, and I've seen a SAM with the Ironworks sword.

Pretty sure I saw one of these weapons drop in a Lv50 (Amdapor? Or was that the Tonberry dungeon? I forget) too, but I can't remember which.