Arcane Crystal Conduit

Dropped from one of the garrison invasion bags got three bags for getting gold rating not sure which level of bag it dropped from bronze silver or gold.

i got this one from a purple bag

I got the Arcane Crystal Focusing Lens from the Silver level Invader's Damaged Cache (blue bag).

got mine from the purple bag but I can confirm doing an invasion leads to this part

did 3 invasions in the last 2 weeks and only got 2 of the same part and none of this part. in fact one invasion of the iron horde gave me no bags with stuff in them . getting these parts are really way way to difficult. I've got some parts but not really close to getting this trade post auctioneer and I've been working the area for a month now.

This is one of the components for the Auctioneer that can be constructed in your trading post. Once you get a [building=144], you will find a broken [npc=87205] on the floor. To fix it, you need to complete the quest [quest=36948] which requires 5 modules. Each module is made up of 3-4 components, which individually drop in specific places. Note that all modules and individual components can be traded, vendored or auctioned.

[item=118375] - Requires [item=118344], [item=118345], [item=118346], [item=118347]. These drop in garrison invasions and in raids. [item=118376] - Requires [item=118197], [item=118331], [item=118332]. These drop in dungeons. [item=118377] - Requires [item=118333], [item=118334], [item=118335]. These drop in Ashran. [item=118378] - Requires [item=118336], [item=118337], [item=118338], [item=118339]. These drop in Shadowmoon Valley, Talador or Nagrand. [item=118379] - Requires [item=118340], [item=118341], [item=118342], [item=118343]. These drop in Frostfire Ridge, Gorgrond, or Spires of Arak.