For a vague idea, I have 83 of the gold turn-in after running Medusa 6-8x a day. I also have around 20 of the SR glaive enhance materials, and have gotten 2 platinum chests (2x SR defender weapon). So I'd still need need a platinum chest drop to reasonably full limit break the eidolon, although I could probably full limit break the weapon if I used the half-elixirs I've gained from the event.