5 figures. at least fight for high 4. take lower if you need the money. but with the new ICANN TLD activity (RACE), this domain is a great one. if your buyer disappears, seek out the companies that are fighting for position in this space... there are many players trying to be the conduit between applicants and Icann. I am active in this space and I believe you've got a great name. research the $$$$ being spent in this space and price accordingly. the app fee alone is 6 figures. the consulting fees are 5.
either way, good luck.