If you want to buy a mobile phone, touch it, play with it and not hear even once a word deal or plan in Poland you go to Carrefour, Auchan, Media Markt, Neonet, Euro AGD with zillion phones. Where to go in the UK?
Not sure how we got from mobile phones to plumbing? Most big home stores like Homebase, B&Q and Wickes etc. will all have parts for showers and taps/ faucets. For a specialist check out if you have a local branch of the "Plumb center" near you.