Um... how about you go farm/quest BLM spells and use the proceeds to buy your dice then? Dice are not an issue. I'm not sure I agree that dice should be priced by level (Courser's Roll and Allies Roll should be cheaper because they are so highly situational), but I have no issue buying dice. Anything you can buy can be "farmed" by getting gil from some other means and investing it in the buyable item you want.
Ammo is certainly the problem today. Steel Bullets are rare enough on my server, and there haven't been any stacks/pouches of Oberons sold on my server in over 6 months. I understand S-E is reluctant to damage the potential crafting market, but crafters are NOT supplying ammo.
I'd be perfectly fine with NPCs selling ammo for a cost that is high enough that crafters could still make the stuff and sell it for a profit. But at least give me the opportunity to buy it. I was lucky enough to get a single Oberon's Bullet months ago, but I sure hope I don't accidentally shoot it because of a macro error, lag, or my own mistake. I'd be very happy to be able to buy a stack and be done with it.