I'm looking at a vintage Rolex on eBay (link: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360279472376&ssPageName=STRK:MEWAX:IT ) and am wondering if there is any Rolex equivalent to the trusted purse authentification sites. I would like this authenticated AND I would also hopefully like comment from someone knowledgable re: the pricing. Does anyone know of any website/person that does this? Someone who is accepted as knowing their stuff?
Thanks!
EDIT: Also, this is a noob question, but it is possible to replace the strap, right? Does Rolex itself replace straps (I want a metal/link strap) or am I looking at something random?
Thanks!

EDIT: Also, this is a noob question, but it is possible to replace the strap, right? Does Rolex itself replace straps (I want a metal/link strap) or am I looking at something random?