No crabs or cookers in Bulgaria? It looks like we will just have to import a few maidens from England. The question is though: Can they survive the summer heat?
Choosing a variety that will suit the climate is most important. With this thought in mind, perhaps grafting onto existing Bulgarian rootstock could be the best option. This is not an easy process for an amateur in my experience, and the only time I tried it, it didn't work, but I'll try anything again for a pint of scrumpy.
Thanks for the nursery link Bulldoggeorge. Another good nursery for rare or old apple varieties, and fruit of all kinds, is Brogdale in Kent.
The Frankfurt area in Germany is the nearest place where they make cider in quantity, but it's apfelwein and not quite the same stuff really.