I thought that most pharmacies sold borax powder or has something put a stop to that? Washing soda should be available from most supermarkets or at least your local DIY store.
For borax you could try " Auro " , a company selling natural paints , check the web .It is used as a preservative for timber . Soda is soda , at least in the chemical term . Baking soda is a food ingredient i.e. it has an "E" number . Washing soda is chemically the same thing but it could be contaminated with impurities .
My excuses for the wrong info that soda is soda.Baking soda is not the same as washing soda as cobalt has stated correctly.
Borax can be obtained from Auro . I bought it myself there , but find the price a bit hefty.
Their trader is " health build " and they can be contacted via healthbuild@iol.ie
Or in Dublin : Klee Paper , 89 North Circular Rd. , Dublin 7 . Ph.: 01-8385943
Nothing to do with water softening I'm afraid! I was told that if you mix borax with icing sugar it's great for getting rid of ants (they have moved in to our front garden in the last 3-4 years and seem to be getting closer to the house).......we'll see how it goes!