The version of the rules I follow, copied I think from a Reddit post, ran:
Described as follows: "Material" - "Conditions"
Core Dynamics Composites, Proprietary Composites - Federation-aligned system, Election, none
Imperial Shielding - Empire-aligned system, Election, none
Improvised Components - System in Civil Unrest state, Independent or Alliance
Military Grade Alloys, Military Supercapacitors - System in War or Civil War state, independent or Alliance
Pharmaceutical Isolators- System in Outbreak state, Independent or Alliance
Proto Heat Radiators, Proto Light Alloys, Proto Radiolic Alloys - System in Boom state, Independent or Alliance
Neither this nor the set in the first post are entirely accurate: I sometimes find MGA and occasionally MS in HGEs owned by Imperial factions, which my rules don't predict, and I just spent today gathering 360 Imperial Shielding from Imperial systems in state None, which isn't mentioned in the first poster's rules.
But the big changes since 3.3 are first, the new emphasis on faction rather than system state - I had a frustrating session on Wednesday trying and failing to get PHR/PLA/PRA from Independent and Alliance systems in Boom, because, I think, while the controlling factions were indeed in Boom, all the other factions were in state None, so not producing HGEs.
And second, of course, that some states - in particular Outbreak and Civil Unrest - are very, very scarce.