Isn't it like 4-5 mil a stack? I think it's better to just contract a craftsman to make it by sending him the materials if you know one.
Man, that's some hefty amount of ammo even for Rng
I use it in very limited scenarios- its not my primary ammo choice for crossbow. But it sure is nice to have some on me as an option for moments like a Dyna-D PLD NM popping Invincible.
In terms of cost- I don't mind paying for rarity and to reward someone for building the shield all the way to the final form. Thankfully, SE changed the math on the synth so that a NQ results in a full stack of ammo, meaning the cost isn't nearly as bad as it was upon release. I would reach out to someone with the tools necessary to make them, if I knew of anyone directly.