I pretty sure there is no way I am going to boycott e-bay over this. But I am not planning to buy any body parts or reliquaries, holy or otherwise, either.
Somehow, I doubt that a bone or dried part of a saint would be miraculous, anyway. Most likely it would be either an animal part or the part of someone why wasn't a saint.
There have been hundreds of thousands of Egyptian mummies dug up over the years, complete with bones. How could you tell the difference between a bone from one of these are St. Augustine? I suggest that without some saintly DNA this would be impossible.
E-Bay is obviously not at fault, since there was a statement that no body parts were included, and no evidence that they were.
These things have been bartered between varoius churches for centuries, by the way.