Broken wheel nut, repair or replace hub, nissan micra 2003?

A wheel nut broke off when I was changing the front wheel. The garage says I have to replace the complete wheel hub (at an very high cost of parts and labour), and that with the Nissan Micra it is not possible to simply repair it. They claim that on the Nissan Micra the old bolt cannot be bored out of the wheel hub. Is this correct?