Jeff, I don't know if you ever got access to anti-phishing's phish archive; but if you didn't, you might put up a donation link on your site and solicit contributions that would specifically go toward paying for access to their database, for at least 1 year. Of course, if their database isn't updated as quickly as yours or isn't helpful for the first year, then you obviously wouldn't continue it...
Just an idea...
Matthew Wilson