Do you mean to get her to fly once, or to fly regularly in service?

If you're wondering about the latter, just look up how much jet fuel cost in 2003 and how much it costs now. For all the nostalgia about Concorde and the conspiracy theories about her retirement, it seems clear to me that the increases in the cost of fuel over the last 10 years would have done for her viability as an airliner even if both airlines and Airbus had all been madly keen on keeping her in service in perpetuity.