You can use my Aeon Labs Multifunction Siren DTH to do the same thing and a lot of other things. All you have to do is use the “Audio Notifications” section of Smart Home Monitor, select “Custom Message” for the Notification, and type one of the commands into the “Play this Message” field.
The commands are fully documented in this post, but some examples are “beep” which uses the beep options configured in the settings and “custombeep1”, “custombeep2”,… “customBeep6”.