The marginal cost of extra Typhoons would be about £45 m ($62 m) per jet (JSF is coming in at $110). Much of that cost would flow directly back to the UK Treasury. We build about one third of each Typhoon, and we'd obviously do the final assembly. We wouldn't need so many because there'd be a common OCU/OEU. Through life costs would be appreciably lower.
And we'd still have an industrial foothold in JSF.