IM stats if i'm not wrong, are obtained from those IM items that comes in boxes, example the daily box where you get the plain white t-shirt. That has a chance of getting stats. You can also you reroll hammers to get (... not entire sure) or simply get an IM stat and just imbue it to the item you want that stat to be.
You can refine from the smith/weapon seller. Weapon refine material is at the weapon store. Whereas Armor and Back item are in armor stores. Catalyst are obtained from farming (Pink/Purple Powder, Lisent Hg/U). Few best places include dungeons where you can get a lot of them at once in a short time.
The other 2 more items are in IM, and i'm pretty sure you can see them, they're called, plutorune (protect your item from degrading or breaking) and Neptunerune (increases success rate by 5%, not sure if have additional effect)
Hope it helps =3