The one below is 'Mystic Merlin'. Not all that much different from the one above, just a bit more red in the purple. Flower size and every thing else is quite the same.
The third one I grow, or grew (maybe), since it doesn't seem to be up yet and blooming although the others are, is 'Primley Blue'. I think this one might be my favorite. It is even more blue than shows in this picture.
As far as a source, Thompson and Morgan carries the seed. I'm not sure if anyone is selling plants, but when they are so easy from seed, it is a much more economical way to have some.