Not really. The native European Weather Loach Misgurnus fossilis is not native to the UK and banned as a potentially invasive species. There are very few non-native fish that you're allowed to keep that would survive the winter. Channel catfish (Ictalurus puctatus) can be bought, but get to about a metre long. I don't think your pond will be big enough. They'll eat anything they can fit in their mouths and have big spines, so I'd think *very* carefully before buying them. Fortunately very few places will sell them. I'm a US native fish nut and I wouldn't keep them.
I've seen Gudgeon for sale (Gobio gobio), and they may be suitable, although they're small (15cm long). Some places are also selling Sticklebacks, although I've never seen them myself. I'd se i you can track down some of them, and have a nice wildlife pond. After my parent's pond got cleaned out by a heron I saw a much wider variety of insects, an I'm sure we had more frogs and newts.
Hi David thanks for the reply so catfish are out of bounds then i have loked at some gudgeon and seen some quite nice ones and do look very simular to a kind of loach i may have a lok around for some many regards brian