here are a few i like:
perhaps one of the following could be added to one of your shirts....
"Ted Kennedy's Car has Killed More People than my Gun"
"When seconds count, the police are only minutes away"
" the right of the People to keep and bear arms shall not be infringed"
"Every person has a right to bear arms for the defense of himself and the State."
Mich. Constitution Article I, Section 6.