The last one I saw for sale was a couple months ago at drmaccorals. I'm sure they still come in on a regular basis, so I'd call or email some of the larger livestock mail order vendors. It's just that very few people buy this species since it's not very flashy, so you don't see it for sale as often anymore.
Beauty is in the eye of the beholder. I really liked H.hippopus and had one (purchased from Harbor Aquatics) until I had a severe alk and pH swing that did it in.