Well my friend, Dragon Fangs can be won as a result of battle from Blue Dragons if you have the Rare Item Ability on. I remember hearing somewhere that if you use GF Tonberry's Lvl Down on it (lower than lvl 10 I think) you don't need Rare Item. You can find them near the Shumi Village or on the Island Closest to Hell.

Pulse ammo will be harder to get though. There are only two places in the game (that I know of) where you can fight Elnoyles - they drop Energy Crystals. One was the bridge in the middle of Esthar City, but as you can't now get there that's a knock-off. The other is in the Lunatic Pandora. I don't think you can get there either...

You can change Laser Cannons or Energy Generators into Pulse ammo but they're also pretty rare.