It looks real and early. That being said, the photo is not good enough for me to stake my rep on it, but it looks right and I seem to remember this seller selling authentic stuff int he past.It is probably worth $200.
Still, for about $200, you can get a signed Hb that is numbered and guaranteed authentic.
Further still, this book, if signed, was signed AS a book, not as a sheet that was bound in, so that is nice.
Yes, as a rule, if they are regular members here, then it is safe to assume that what they are selling is authentic. I'm trying to figure out who Captain Fantasy is, but I do remember the name from ebay and know that their Buk stuff is nice...
Also, as a rule, anything signed that you see on ebay is authentic unless you see a posting about it here. We take forgeries very seriously. The first time they are seen, something is posted here. We also let the person selling the item know that it is a forgery and ask them to remove it. If they do not then usually someone here will take steps to make sure that they do not sell it.