The MGS keeps a list of suppliers of plants (or seeds) suited to mediterranean climates, for this forum. I have attached the current version. Please note that I have not checked details with all individual suppliers.
To see the list, click on the Supplier List blue link below this message.
I'd be very grateful for any further recommendations, particularly in the thinly covered countries! (In California I have already whittled down the candidates to a manageable number as there are so many possibilities - but there as elsewhere do please post any obvious omissions.)
Also, do please post any particularly good experience with any of these suppliers. (If you've had bad experience you may prefer to email me privately.)
I will revise the list from time to time, in the light of your postings. The current version includes all recommendations received up to and including February 2020, among them several recent interesting additions in Italy.
Incidentally, whenever I update the list, the "number of times downloaded" zeroes back to 0 - so it very much underestimates the number of people who have looked at the list (this time when it was zeroed, my running total of all previous downloads had got up to 3,064). And if the number is low, it means the list has been recently changed.
Thanks, everyone!