A lot of people are asking me where to buy Atom Republic items. Until we have a public space later this year, you have to buy them from the Navigator and from the shopping mall.
If you're in NA, you can buy them from the navigator: in the shop column, navigate to the "New & Featured" section, then "New". Click on the Atom Republic icon on the 3rd row. The Radpetz can also be purchased from the "sidekicks" store in the shopping mall.
In EU, the Radpetz and dances are in the "Stuff" store, and the jackets and moustaches are in the "Threads" store: both stores are located in the Shopping Mall East.