Alisdair..That information about Phyto sanitary regulations is EXTREMELY helpful... Yet, when one arrives off aircraft from third countries there is the big bold notice about importing plants and SEEDS... but I do know friends here in Spain who bring seeds (via UK) in their suitcase from all sorts of amazing places (mostly parts of Africa) and just hope for the best!
You are right the only time I have seen seed for sale of this beautiful Salvia is on an American site.
I first saw this plant growing wild on the dormant volcano Pululahua in Ecuador. It was a glorious bright blue, a beacon in the Cloud Forest. I tried to find seeds but it wasn't to be.
You have been really helpful ......