A friend sent me this link, and I noticed that on the far left of row 2 on this page, there is a small photo of the Barnabas Collins Halloween costume:
http://www.retrocrush.com/archive2003/costumes/tv.htmlI seem to recall reading about this costume years ago, and how impossible it is to find. I would think that the cheap, rapidly deteriorating materials these costumes were made of would put a fairly low ceiling on their market value, but apparently that is not the case.
There are some weird and tacky attempts at costumes here, including several from other TV shows that I know are popular among DS fans, such as Samantha from Bewitched, Morticia from The Addams Family, the Groovy Ghoulies (shown on another page,) etc. Everyone will have their "most bizarre" item--I think my choice is for the truly frightening Laura Ingalls Wilder costume. The weird "Greg Brady" outfit is a close runner-up, I have to say.
G.