Thanks Royston & Mike.
Have stared long and hard at CORBETT and CONNOLY and could not square the circle, so to speak.
However, during another STINT (yes, that's STINT!!)looking at it - a Eureka moment!
26a is not SNIPE, It's STINT (a small wading bird) - which would, of course, give CORBETT for 11d.
Must now plan how to spend the £500. Good luck to all. Hope my trials and tribulations might have helped. Chris.