I bought from the same guy... I'm almost certain of it. He told me they had been sitting in his house for years when he decided to start selling them. I didn't pay much more than the price you got yours from.

If you read the forewords of some of the guides available you can get a good grasp of how price can be affected by a large find, especially when someone floods the market. Its always good to ask here before making a purchase and to ask yourself why a "high value" chip isn't getting many bids.