I am a dirty 60 year old who is looking for young girls - will i do..
Ok well if failing that..
we go to Burgas a few times each year and see many young people out and about...so there are young people there and maybe it may be worthwhile to visit local cafes etc to have some chance meeting etc. To sit at home or to wait to meet young English people is not the way to go.
Do you speak Bulgarian? If not then maybe look for a teacher who could then lead you to contacts..many chances -but in a new country it's up to you to make the first moves especially as Bulgarians tend to be 'unfriendly' but from experience - break through that barrier with a nice smile and you will find warm hearted people.
All the best to find new friends.