Nope, not seen them in any UK supermarket. But you could try Googling ' Greek deli online UK ' or have a look in any Greek/Turkish shops you find locally. My local halal shop has all sorts of cheeses for example.
Well they do free delivery so if They deliver and you can make up a £50 order of offers and bits and pieces, might be an idea. I got one of those huge Lindt lindors today for £10 i.e. 4.99 off, for example. Lots of Waitrose stuff is price matched to Tesco.
A friend was going to Waitrose and got one packet of cheese for me. We had Saganaki for dinner tonight, it was like being on holiday on a Greek island, the taste bought it all back. I dusted it with almond flour but I don't really think it really needed it. Yummmmy.