In reply to galpinos:
> Take your boots into a decent shop...
"Decent" is key! You do get the occasional huge exception to the rule, but a lot of people working in your average Cotswolds don't have much real expertise - you hear them giving terrible advice all the time on generic stuff. On something as bewilderingly technical as crampons you would absolutely need an expert. When I first moved to the UK I went to get some hiking boots (mud and water not being big concerns in Australia!). I spent years trudging around in super heavy (1 kg each at least) B1-rated mountaineering boots, because I said "maybe, I don't know" when the kid asked if I would be using crampons!