Sage jiraya (everything except 9tails), asuma wb (9tails), shurado (pvp), 1.0 jigokudo (everything except 9tails) - those are ninjas from tendo treasure that are good for fire main, Ive put area of usage in the brackets.

Later on you will get most of the ninjas from first 2 treasures for free (from elite instances/plots/shops). If I were you, i'd wait for kage treasure, since every single rare outperforms ninjas from tendo treasure. If kage isnt released yet in your version, save scrolls until they release it. Skip seal, tendo and sage treasures altogether.