If you fish, then the reagent can be found in Fishing Chests in: Storm House Life HouseMyth HouseMassive Fantasy PalaceThe Sun Palace Polarian Shipwreck Gardening;
One plant currently drops the reagent and that is theJewel Star Blossom.
A few packs also have the reagent;
Wysteria Lore PackRoad Warrior's PackMega Reagent PackImmortal Lore Pack Whether these methods are easier is up to you to decide, but these are currently the only other alternatives to getting the reagent.
There are bosses and mobs that drop the reagent as well if you're interested.
I have been getting a lot of steel by fighting the storm brigadiers, in walrusburg harbor in Polaris. They drop the steel almost all the time. I also do the steel chest there and the wooden boxes. Steel can be found inside of them also. There are a lot of pearls all over that area also. I fight the penguins, grab all the pearls, do steel chests, and get the wooden boxes. I then Change realms and do it all over again. I get a lot of my pearls, steel, cat tails, shells, and other rare reagents there. While people tell you to get steel from the jewel plants, you have to get them from Farley's pack in the crowns shop and it is very rare to get them in the pack.
