As far as the PAL papers go, if they were made in Yugoslavia, the Efke / Fotokemika factory is in Croatia, which was once part of Yugoslavia. I am fairly sure you have Fotokemika graded paper of some sort on your hands. The current Varycon is beautiful in lith, and Emaks is supposed to be very good.
I have a friend who has blue boxes of Seagull that still prints great. Agfa Brovira is gorgeous paper. I have recently broken into an old box that fogs very badly with standard chemistry, but looks really cool in lith developer.
Sounds like you have some fun printing times once you get into the darkroom!
- Thomas