Antibiotics are fairly cheap if you buy them under non-SHTF circumstances from the right sources, but I learned a few hard lessons trying to deal with regular pharmacies on it. Total jerks. Seemed convinced that I was either trying to get high or trying to set them up.
Online veterinarian suppliers seem to be the ticket unless you can send someone to hand carry the stuff over a border from Mexico where most common (and needed) antibiotics are available over the counter for cash at pretty reasonable prices.
The issue is, that's trade supplies, right in the league of "thanks for your shit, now get the fuck out". You want to be real cautious about tipping your hand on a lot of that kind of stuff, especially pain meds. Otherwise, people with "needs" come out of the damn woodwork to beg, borrow, barter and steal to relieve you of that stuff. Then its gone when you need it. Less so with the antibiotics though.
Moonshine still is pretty high on the list. Those require a certain skill level and experience to operate.
Those people in Bosnia were for the most part lower middle class in the best of times, so certain ghetto rules apply there that might not apply elsewhere. Too bad the guys lost contact, but at one time, we had a couple of Lebanese Christians circulating around AW and here right at the beginning. One of them had a lot to say about how they organized early in the war. With them, everything was organized and coordinated, with the wealthier mafia types paying for everything, the lower class types doing the grunt work, but not expected to pay. Attacks or thefts within the ranks of the Christian neighborhoods under siege were rare because if someone did that, and got kicked out, the Jihadis would have at them. Everyone was actively doing things to prove their commitment to the community because they wanted the community to back them up. They could not afford to play that dog eat dog mentality. That level of selfishness was considered to practically be an act of treason.
When I participate with a group, I am pretty generous and share everything of value that is not highly personal or of particular legal liability. I expect the same in return. Call it micro-socialism, it is what it is.