Hi Anne,
I was so delighted to see these blue and silver pieces. I was on a school trip to Greece about 35 years ago, and I bought two - (a large vase for my Mother and a small bowl for myself). I bought them at an agora or outdoor market in Athens. They were new, and medium priced. I don't remember them having labels, though.
Hope this helps narrow it down a bit, anyway...
Huronia