No easy way to get that 'fast'.. will probably take at least a week unless you've got some kind of exploit. Easiest way for you would be to buy a 10k account that has the URL unset, then simply delete your old account and reg your old accounts URL to the new account. You'll have to re-add your old friends but that's a minor problem eh?
10k friends in a week will get your account deleted anyways - infact 5k up in a week on a new account will probably get it deleted too