You should have gotten the mace when you defeated Barnabus. Are you sure you got the loot bag, and didn't check the area for other things first and forget about it? Short of a bug, if you got it you should have it until you turn in the quest.
I defeated Alutiiq long before making it to the harbor. Again, the mask should have been in a loot bag when he was defeated. It goes directly into the quest item list, so you should not have been able to get rid of it yourself.
Did you not get it at all, or did you have it but now it is missing?
For Moor, if you leave the harbor, turn into a dragon when you are past the ant-dragon shield and then fly south east along the shield until you reach the cliff. You should see Moor's cabin on a ledge near the water line (partly in the anti-dragon shield, but mostly outside).
If you climb the mountain by the slayer camp and jumped down into the water you wouldn't have far to swim to get outside of the anti-dragon shield, then transform briefly for a short flight up to Moor's camp.
If you remember where you found the imp Alrik, Moor is directly across the water from there.
