All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.
The sound of cheeping is not among the forbidden musical instruments, and it is not forbidden to listen to it. Therefore, it is permissible for you to have these bells because in principle all things are permissible, and it is only what is forbidden in the Sharee'ah that is impermissible.
Allaah knows best.