I would think this is a case where the Magnetics on ebay made so much money that every collector out there with one has thought about selling it. I would lay odds on that's what has happened in this case.
These types of records are out there in collections. About 2 years ago i was round a 'quiet' collectors place, who doesn't d.j., normal every day kind of job. I was blown away when i saw a few of the records in this persons collection, there was a 'Lady in green' there. So you imagine the temptation to sell, when you've just seen one make $8000.
In the case of the Danny Moore, i got a 'demo' from long before they showed up, the vinyl's the same as the quantity ones, they're real.