I use stainless steel or ceramic usually. If you go with better name brands you can be sure they are stainless steel. I have used some from Lixit, King's Cages, Midwest Pets, Prevue, etc. One of my go tos for new dishes is here; it is a US website but might give you some search terms to use Dishes - Windy City Parrot
I do avoid plastic whenever possible just because I don't like the rough feel it gets after a while, and I like anything I can throw in the dishwasher. Water bowls do get dirty faster but ideally water should be changed at least once a day regardless, and I know with bottles I tend to not change them as often because there's still "clean water" left.