I am not seeing chaos swarms listed in stations that have them. Chocolateer gave me a lua string to use in console which lets me buy them but they aren't listed as available. Happened initially in Arta Cael L-2, but also in, I think the sectors are, Arta Caelestistis J-11 and 12, later in Dau.

lua PurchaseMerchandiseItem(2019591226,10)

gives me 10 chaos and charges me for them, no msg.

looks as tho' I am seeing the same large port equip list everywhere?

I have screen shots if needed.

Are you using any plugins? If so, disable them and see if you still don't see them.
Chaos Swarm missile launcher is listed for me in Arta L-2, J-11, J-12 as a Large port weapon. It is the last item in the list in all three stations.

I removed the plugin folder completely so not a one and chaos doesn't show in the menu in either Arta Caelestis J-11 or J12. ??