Opinion request

Group,

I have been trying to put together the components of a CNC router table.
Here is an item on Ebay I wanted for the Y axis.

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=582672377

I haven't gotten my hands a catalog of linear components as of yet and
would like to know if the selling price was justified or if it was Ebay
madness. Everything seems to go for $100 more than I think it is
worth. Do I need to adjust my sights?

Thanks,

Rich