Sometimes it works the other way around - in my view we should have developed the Buccaneer Mk 3 instead of trying to buy US F-111s or joint compromise in the Tornado GR1. We could at least have sold them to the Germans, Italians and Saudis.
We could easily have built the Viggen under license (perhaps with UK equipment) it would have transformed the RAF in the 70s. Replacing the Lightning as an interceptor and also filling the role of the Jags and Harriers.It would have been quite a frontline with the F4 and new Buccaneers.
In the 80s we should have gone F-15C - (or even better for the UK F-15D with the radar in the back) probably with the conformal tanks that were later fitted to the Es