Don't let the threat of a little radiation scare you off. You may wish to consider a Family Radiation Measurement Kit made by Bendix during the Cold War. Mine looks exactly like the one in the picture:
http://cgi.ebay.com/Bendix-family-radiation-measurement-kit-early-1950s_W0QQitemZ200015329103QQcmdZViewItem#ebayphotohosting
http://cgi.ebay.com/Bendix-family-radiation-measurement-kit-early-1950s_W0QQitemZ200015329103QQcmdZViewItem#ebayphotohosting