i live in the States so i wont be any help as far as giving you the name of stores to go, but i had one of those and i found it a real pain(the fine mesh type ones) they collect every little thing and clogs very quickly and i found not easy to clean out after. I found the plastic ones that have larger holes that DONT collect soap scum along with hair. I have LONG brown hair so i would have a heck of a time with clogging drains. If you can find the plastic ones that go over the top of the drain hole instead of mesh inside the hole i feel they work better.
hope that all made sense?