On Wed, 28 Oct 2020 04:41:06 -0700 (PDT), "Peter W."
wrote:

https://www.amazon.com/American-Scie.../dp/B003VP0DQ2

Not so hard.

Cool, I've ordered the same thing (and in white) from Amazon UK. ;-)

Eschew needless complexity - William of Occam

Agreed, if at all possible and as long as it works. ;-)

Do you think I'll need to limit the voltage across the buzzer (2 (/3)
diodes in series in parallel with the buzzer?) and that the existing
bell draws at least 25mA?

"* Minimum Input Voltage: 1.3V* Maximum Input Voltage: 2V* Current
Consumption: 25mA* Nominal Output @ 30cm: 75dB* Output Frequency:
400Hz* "

Cheers, T i m