Have just been out with friends walking our respective dogs. One who's really into dog training (she has Welsh terriers) still seems to think we're just useless at training them rather than the fact that cockers can just be down right difficult (she can't get past that oh so innocent butter wouldn't melt in my mouth image of them).
I had heard that of all the gundogs can be are the most difficult to train, but don't we just love them.
There are loads of sites I've found selling the whistles I want at the price you quoted Ian, and have discovered there's a gun shop in Roath, Cardiff, which isn't too far away. Too be honset I know it won't cure his 'deafness', but its something to 'distract' his attention every now and then on to me and if his deafness does take him too far at least he'd know where I was (the other day when he did a runner, once he removed his nose from the ground he'd become disoriented and as it was very windy he couldn't hear me calling as so followed a person nearby wearing the same jacket!)