Materia I-IV

So I've been grinding out the ARR Relic Weapons for the glams and I've hit a roadblock of sorts I'm hoping the forums can help me out with.

The notorious Novus step of grinding out Alexandrite and Materia. The Alexandrite isn't a problem as I just do my Blu mage weeklies, I think I'm sitting on about 120 right now. It's the Materia that's the issue.

Is there no other way aside from the market board/spirit bonding old gear to get this Materia? For the Materia Is and IIs I've been running command missions with ilevel 29 gear on and for IIIs and IVs I've been grinding out Urth's with some dungeons thrown in to mix things up but it has been a slog to say the least.

Does anyone have any tips on grinding these Materia? I would just buy them off the market board but there aren't nearly enough and it would cost me a small fortune. I do think SE should probably look into this oversight as everything else regarding this weapon is relatively simple and dumbed down from the original version to the extreme except for this.

Not 100%, might check later, but III and IV may be available through Firmament scrips. Do some crafting or Diadem gathering, or just hang around for fetes, exchange for Brass Sky Pirate Spoils, can be exchanged for materia.

No apparent other sources for I and II. Technically II may be rewards from a couple exploratory voyages, but that's pretty limited access, and why when you could just send ships out on higher voyages for more valuable rewards..