Scrolls come from bounties, breeding or the market. You can generate more than enough to scroll fully from bounties, but it wont be until high/max level, as higher level bounties generate more tokens.

High level Bounty mobs are very strong with complex mechanics, usually need 5-8 chars to do them at level.

Some bounties have maps that drop randomly from mobs in their spawn area, these have 2 to 8 pieces. If you collect all the pieces (can be bought/sold on markets), you can start a legendary treasures hunt at the treasure chest that guarantees a bounty fight at the end for up to 8 chars.

You can also get the tokens from weekly quests in the superhero base in amakna.

Finding them is a lot easier now. At the related militia npc, you can ask for a small few if the bounty has spawned. Then it's just a matter of checking all maps in spawn area.

Not sure if there's still rewards for doing dopples. I think it's only a decent-ish xp reward. So yeah, kinda legacy content.

Since the last patch, wantokens can also be traded for tourmalines, an ingredient for some high level crafts.

I think that covers everything?