I've gotten some of those, though I don't have any to give. My best advice is this: read the wiki, play offline and start manipulating world tendency. Almost all of those can be gotten from Crystal Lizards, and if you make your world tendency Pure Black, they're almost guaranteed (in my experience) to drop. In case you don't know, the blacker the world tendency, the better the drops. If you need help hunting the lizards, look at the wiki and guides online.
For instance, if you want Pure Darkmoonstone, do this: get World 4 to Pure Black by using a Stone of Ephemeral Eyes and killing yourself a few times, then go to 4-3 after you've finished the boss. Kill all the manta rays, and then go stand on the little hill next to the archstone. Get a good bow (I used the Lava Bow), and then fire an arrow into the one crystal lizard you can see. He'll skitter off, but if you wait, he'll reset and leash back to where he started. Fire another arrow, and then repeat until the little fucker's dead. When you've killed the first lizard, rush forward and kill the other one (when there's only one of them, it's fairly easy to do). You'll get two Darkmoonstone drops, and if you're on Pure Black, you're virtually guaranteed to get at least one Pure.
There are similar strategies for almost all of the other ones you mentioned. Some of them are even easier, like Pure Marrowstone, which can be found as a treasure in 5-3. Pure Greystone is also not very hard, there's a very simple way to get one (again, look at the wiki!). If you've already burned all your lizards, start a new game or do it in NG+. The only one that's really tricky is the Pure Bladestone, which only exists as a very rare drop. Either find someone online to give it to you (unlikely), or you just have to buckle down, black up your world tendency, level up your Luck and use the Large Sword of Searching.
This may sound tedious, and it is a little bit, but it's the Platinum trophy for Demon's Souls we're talking about here. If you expect it to be a simple thing to get, you've been playing a very different game from the game I've been playing.