The rewards gets tweaked/shuffled around a couple of times later; one a minor change, the other being far more notable.

The first tweak happened with Amphisbaena (3 raids from now); the last copy of the eidolon is at 57 red souls instead of 70. The last SR weapon copy is at 66 instead of 74 red souls. SSR weapon's still at 100, so if you want it, things are still the same.
Still need 150 blue souls for eidolon and 200 for SSR weapon though.

The major change to the rewards lists happens with Barong (2 raids after Amphisbaena).
Blue soul list only has 1 copy of the eidolon and weapons. 35 for the eidolon, 50 for the SSR weapon. Draconic eye shard at 200.
Red soul list has the rest of the copies, but interestingly, not enough copies of the SR weapons. You'll need to roll 1 copy from the gacha to max out an SR weapon. You can still max out the eidolon and SSR weapon through souls though. 55 red souls to finish the eidolon, 40 for the SSR weapon. Draconic eye shard at 90.

(ok, to be complete, in between Amphisbaena and Barong is Icarus. Icarus added the draconic eye shard at 170 blue and 90 red)