Hey Jordy,
Please forgive my bluntness, but run away from this one. Glad that you asked here, there are several CGN members that are very knowledgeable on Westley Richards guns, and I expect some will chime in.
Is it an authentic Westley Richards? I sincerely doubt it. There are so many red flags I'm not sure where to begin. It is a low-cost, machine-made, gun that has been bubba'ed and possibly mis-repaired. I wouldn't trust my fingers, eyes, or life putting a live round through it. The metal-to-metal fit on a WR should be near-perfect, here it is sloppy and uneven; the Greener-type crossbolt should disappear into the fences, instead of ill-fitting; the top-lever is not of a shape that appeared on any WR gun that I know of or can find pictures for, WR top-levers are wide. Some of the screws, if original, seem to be of poor quality. The engraving is poor. The company name and address should be engraved on the rib, not stamped on the barrels. Someone has been practicing checkering on the butt stock, no WR ever looked like that. There is more to comment on, but I'd better stop here. You get the picture.
I wholeheartedly recommend shooting with British doubles, and I am a great fan, and user, of British hammer guns. They require careful feeding, but otherwise can provide immense pleasure and satisfaction of ownership. There are bargains to be found, especially if you are willing to put up with some of the idiosyncracies of vintage guns. But original quality is key, and that gun does not have it. Find something better.
If you want to see and examine interesting doubles, try to attend the upcoming 7th Annual Double Gun Classic, in Oshawa on the 10th of June (see the thread on the subject). There will be lots of friendly folk more than happy to provide help on what to look for in a vintage double.
Again, apologies for my directness, only wanting to help a fellow CNGer.