£51k for a sea dweller, I think that may Be the problem!
In all seriousness, that seems steep for one of those and I would imagine that anyone prepared to drop serious money on one will have alternate contacts who may be able to source one for less.... That said I just don't get the whole hysteria associated with comex and issued watches.
Based on my aforementioned view I'm probably the wrong person to ask, having given it serious consideration I believe that the decimal place is quite possibly in the wrong place and will be adjusted very soon, still too much money at just over £5k
Paul