I bought a bouzouki in Athens in 1969, on my way to Israel. I used it to play Celtic dance tunes when I got a job with the show, From Then Til Now, which toured army bases and kibbutzim for over a year.
I used the standard tuning without dificulty. I don't know when Irish musicians starting using them. I heard none during the two years I lived there in the late 60's. My plan, when I bought it, was to play Greek and Lebonese music but, I never got around to that.

                        Mike