This is a tough site to project a value for. Since you are letting handicappers redirect to their own sites, it is debatable how many players you are signing up through the site – and thus it would be very hard to tell how much money you are making from the site unless you can divulge those details.
It’s also not clear how much maintenance is required – nor if additional sports can be added.
I’d say you would have a bit of a hard time on eBay since most people viewing the auction would be confused, unless they just wanted to own a site for the sake of being a webmaster.
Feel free to PM me if you don’t want to post further details here.