If you want to peddle these instead of mining, may I remind that these are out of stock in Europe as well.
Except there the going price is 600-700€ or more per card. That comes to a minimum of $850 dollars.
Buy a card from Newegg and people in Europe will snatch it up in an instant if you sell it on eBay for 599€. You'll make a few hundred just by ordering stuff.
Yeah but selling anything of this value outside of the US can be risky due to the fact the only shipping method that will even provide you with the proper tracking to cover you with PayPal is USPS Express Mail and then you have to deal with customs and the buyer having to pay tax on a high dollar item makes it a very expensive purchase for them which once they see how much the tax will be may decide to refuse receiving it. Yes you can falsify the customs form and either undervalue it or mark it as a gift but you have to decide whether its worth it to risk getting caught. Packages can also get "lost" fairly easily going to certain countries in the world.
Selling within the US is a lot safer but even then on a $850+ sale you risk losing all the profit you make on multiple sales just from one PayPal claim against you. You would also have to deal with the fact that even the manufactures don't have 6990's for RMA without waiting weeks or months so if there is an issue with the card the buyer will be sending it back to you to take care of.
After eBay fees, PayPal fees, shipping and insurance cost your only looking at making around $75 if you sold it for $900.