Found a Ranchero to buy, Asking for assistance to properly identify it..

HI,
I'm hoping some of the experts out there in Omega land can lend a bit of expertise.
I've found this post on Google+ https://plus.google.com/106629441005549969231/posts/3TX7Z97woTZ
The guy is in London, where I am, and from what I can tell looking at the post everything seems to be legit with the watch.
I've clicked on the photos, scrolled through them and I've not found anything which sets off alarms.

He's not listed a price so I'm guessing he's hoping someone will pop a number that pleases him.
Could anyone shed any light on if the watch looks legit and if so what kind of money should I offer him? I was thinking 500GBP ?
Any help is appreciated.

I know nothing about these, but id be surprised if the hands are original given the difference in lume colour between them and the dial....

Here's mine for comparison. Hands, if original, have certainly been relumed with what looks like Liquid Paper.

Thanks Mothra and haga888. Would the hands having been replaced have a huge affect on value? And what you think would be a fair price for the watch as it sits?

I would let it slip, the lack of the original hands does decrease the value of the watch to a large extent.