Yeah, the diamond industry has done a pretty good job of portraying manufactured diamonds as fake and worthless, so most jewelry and diamond dealers won't deal with them. When my wife lost the diamond from her ring a couple years back it was impossible to find one, and some jewel dealers seemed offended that I would ask for such a thing.

It's really unfortunate, because the diamond industry is notoriously evil (blood diamonds, De Beers, etc), and science is awesome. We really wanted a "science diamond"