Simplex Fire Alarm Where Can I Find This Fire Alarm?

Where can I find this fire alarm? - simplex fire alarm

It is a simple doorbell / alarm combo cable. I decided on a bell, because the horns hurt my ears worse than he-double hocky sticks (double hocky stick means 2 Ls.) Especially in my old school. Where can I get this warning? I can not be used eBay, because someone could give me predator. I did this before, but no response has been well received. Please help me!