Are these aquired from gathering? Googling isn't really coming up with anything.
Converse with fellow players
It's not a gathering item. If it drops in the same way as JP, it should drop from random enemies of Forest, Tundra and Ruins, at a very low drop rate. A quick way is to check up personal shops, but I guess it has premium price now
Daily crafts can also reward Naverius and other planet crystals.
In the JP version, the rewards are linked to specific days. On the 4th, 9th, 16th, 19th, 21st and 26th day of the month, the daily crafts can reward you with planet crystals.
Going to assume the monthly rotation to be present in the NA version as well, but I have no idea if the rewards per day matches with JP's.
The 9th day daily crafts seems to be planet crystals as it is in JP.
Still, this order assortment seems to be made by just removing two "old type" weapon craft orders from the JP list.
This means we'll never have an access to the Lillipalium rewards for completing 7 or 8 orders like in JP. But honestly speaking, this only hurts in long terms. One year later, I'll be playing NGS, so it's not a big issue for me