I know this is a long shot, but don't think it's impossible.
I have very low mileage(shutter count - less than 2,000), like new D4, 1 year old(no longer supplied with XQD card and reader, but I'll include SONY reader and 32GB XQD card) and want to trade it for your Nikon D810. I'll post photos if needed.
For established GetDPI members only, PM or text to 916 402 8830. I'm in Northern CA. Thanks for your consideration.