I'm not sure about the Austrian vereins; but the Dutch, Belgian and German ones offer yearly free/or smal fee vaccinations-days for members. (yearly membership is usely around 50 euro's). Since all are connected to the bigger EE association; I guess they all kind of offer the same things. Have the same guidelines. But I guess it also changes from local verein to another. In my local one everyone is 70+ and noone uses internet.. so I actually had to visit their meetings to learn about those vaccine-programs and their (and then mine) personal vet. They don't have a website and even joining was done by sending a letter heehee. (That reminds me; I have to go call the leader on his landline when the next meeting is haha) Getting information and their great knowledge of 60+ years breeding animals can take some more effort then "just a mouse-click away".
If it is the same as here; fowl vets are hard to find; the ones that excist often only come over if you have over 200+ chickens for your egg/meat business.. they work for proffesionals. That's why these vereins hold these days. Or some vaccines they get send from a vet by mail and give to the members to administer themselves. It's worth it though. I eventually have found a fowl vet nearby.. the same vaccine costed 124 euro more due to the money you have to pay for the vet's her time.. through that verein it was 1 euro per animal
I spontanously forgot the English word for verein. Sorry. Association?