That is the location I found some at, the one you mentioned is one of them and can be broken down into 80 pieces. The Gold Gear looks very similar but is smaller and doesn't have some of the gem looking decals on the model. Not every I found in the story areas can be broken down, I was very disappointed to find out you cant break the shield Boss pieces..
I only have a couple mods installed, I can get a full list and a screenshot of the gear once I'm home, but none that should have changed that or list it to my knowledge. The ones I know for sure im using (but not the names) are a bed respawning one, one to reuse skeps, and a bee cosmetic. I'm want to keep the game as close to vanilla as I can.
Edit: Checked mods page for those 3, BedSpawn, SkepDrop, and BuzzyBees. None say anything about adding relics or allowing more things to be broken down.
Edit 2: Only other mods are for the map for multiplayer and don't affect items. Also attached the picture of the Gold Gear.