You should buy distilled water and either (1) add appropriate amounts of brewing salts or (2) mix with appropriate amounts of bottled water. You can find the water anaysis for various brands. It would be a bad idea to use Fiji water by itself, unless you want a lot of bicarbontes (140 ppm) and a high initial pH. Evian is even higher at 357 ppm for HCO3.
Here are the water analyses for several common bottled waters:
here is another source: http://www.finewaters.com/
If you dillute distilled or RO water with bottled water, and you know the concentrations of various compounds in the bottled water, you can figure out the mix ratio to approximate a target water profile.