Congrats on your new baby!
You can get Nutrical online if you cannot find it locally. I got mine at drsfostersmith.com for like $7 with free shipping. You can google it for other online stores that carry it.
I would keep your new baby on what he's currently eating and let him settle before slowly changing his diet. But EVO and TOTW are both good foods that would be fine for him. EVO has recently been sold to Procter and Gamble though, so I won't be buying it anymore- the quality is most likely going to decrease. I bought a big bag to stock up.