Try the coffee from roasters local to you. They roast and taste coffee with tap water similar to yours.
It supports local businesses, and you negate one of the hardest brewing variables water. Trying to standardise water is such a waste. Deionised water and third wave packets or buying bottled water is a terrible brewing experience, expensive and awful for the environment.
They will likely have house roasts selling more traditional blends, mainly to local coffee shops. They will also have lighter roasts that will change through the year as they get different beans.
I like this approach, as I've found popular roasters in London don't make good coffee in Scotland. We see the same thing with tea blends. Every supermarket stocks local blends for standard tea.