Where do I find the Morph-Topaz Ring?

I'm level 40 and I'm trying to get 2 morph-topaz rings for a build I'm trying to get. However, they're extremely expensive for me and I'll rather try to find them than grind the reef next to Selchar. Any good loot chest locations where I can find them?

 

Two things to note:
1- Morph Topaz is part of the morph set, and originally you could wear two of either ring in the set (Topaz & Emerald). However with Fruma wearing two of either will give you massive debuffs.
2- Caves are the only place you can get tier 3/4 chests, you can find them in your content book. If you are looking for items, look for caves in regions around the item's level.