The scanner cannot be made to beep but the computer it is connected to can be programmed to trigger the system sound or to play an audio file recorded in a container field to sound such an alert.
Will this be a scanner attached to a regular computer or would an iOS device be used to scan the barcode? If a computer, almost all such scanners function in keyboard emulation mode--which means that the data is input just as though someone used the keyboard to rapidly type in the data encoded in the barcode.
Here's a thread with some script examples for automating the scanning process for scanners functioning in keyboard emulation mode. You won't be able to use those scripts as given, but they may provide enough info to point you in the correct direction: Need help writing script to integrate barcode scanning
Yes a scanner attached to a regular computer