I will be getting my iPad 1 replaced under warranty and won't be opening it and selling to upgrade to the iPad 4, just wondering what you think I could get for the 1st gen 64gb 3g unopened
$250-$300 seems to be the going price for completed auctions on ebay. There is a small niche of people that are still interested in the iPad 1 because it does not have a camera. Many people that work in R&D facilities and such.
If its a warranty replacement then *usually* its not truly "new and unopened". Since it was a returned unit that had its outer shell and battery replaced. However, if it came in a shrink wrapped standard retail box then maybe you can get an extra $30 - $50.
Some posters report getting new units when buying refurbs.
I would be surprised if you actually get a NEW first gen iPad. That would require them still making them. Most likely a refurb with full warranty. But I've been wrong before.