hmr 20p a pop at northampton gun.
Regarding which is best, it's horses for course.
Despite some fanciful claims across the net, realistically the .22lr is a shorter range tool, great for really quiet bunny bopping with subs, say 50 to 75 yards for most half decent mortals.
The .17 is fantastic on crows, magpies and other wary quarry for much longer ranges, say 75 to 200 yards (much further for some) and is fab for shooting down the length of hedgerows.
It is noisy though and isn't much use around buildings such as farms because it can be quite intrusive.
If I could only have one, it