Maybe pay for one but also ask the police department to have another driving around. They people attending are tax payers in the community.
All the men in the congregation should be made aware.
The congregation should be made aware, and be made participants in safety measures. They should know where to go, how to exit quickly, what doors to lock, etc.
If anything happens, their escape should go off like a drill.
All adult members of the congregation should be trained and armed.