Transaction
Transaction is the older brother of Supply chain, with harder preconditions and better things to get if you're willing to fail the quest. Packages in Transaction can provide you with artifacts and guns.
The gimmick of Transaction specifically is that there is a traitor squad which will change factions. That's actually why the Transaction is happening - a group of stalkers want to change faction. People get very confused when they see friendly faction as target in description; it's fine, they will switch sides.
What is funny, I now see that these packages do scale exactly how Neutralization does, but since the precondition is so high, you won't bee seeing level 1 of these packages.
List of guns is too big, but it's nothing extraordinary. Here are all the artifacts you might get:
[f_gt_artifact]
af_itcher
af_blood
af_electra_sparkler
af_cristall_flower
af_medusa
af_night_star
af_dummy_glassbeads
af_dummy_battery
af_soul
af_pin
af_mincer_meat
af_sponge
af_lobster_eyes
af_vyvert
af_cristall
af_bracelet
af_ring
af_electra_moonlight
af_empty
af_gravi
af_eye
af_dummy_dummy
af_fuzz_kolobok
af_fireball
af_baloon
af_electra_flash
af_black_spray
af_full_empty
af_gold_fish
af_fire
af_ice
af_glass