Rating Newest Oldest. Best Answer: You can probably buy borax in the same store you buy laundry detergent. It's called 20 Mule Team Borax. If you can't find it in your grocery store, it's possible borax is banned in Australia...as it is in some parts of Europe.Warning: borax is a poison. I don't know what you intend to do with the silly putty, but I would not give it to children to play with.t's called 20 Mule Team Borax. If you can't find it in your grocery store, it's possible borax is banned in Australia...as it is in some parts of Europe.