Seems to me I've seen Efke (albeit not the whole line) at Film For Classics.
That said, Efke is good film, cheaper than Kodak, and fills a slow-film niche that no other company attempts to cover -- the only ISO 50 alrernative is Pan F+, and there is no alternative in ISO 25 (unless you're willing to spend time and money trying to get microfilm to behave like pictorial film -- I speak from experience in saying that's not easy). APX 25 is long gone, Panatomic-X even longer; Tech Pan will be out of stock by the end of this summer. The only other product of any soft left in that market is Polaroid's pos/neg films, Type 55 and 665, and those are rated higher than ISO 25 (665 is marketed as ISO 100 for the print, as I recall).