At the risk of doing the unthinkable and just trying to (partly) answer the question asked without making a judgement call, I would suggest looking at using something like a 4093 (Quad NAND circuit), These are a few pence / cents each.
The 4093 is VERY easy to use - one capacitor and one resistor will turn one of the gates into an oscialltor, you have four of these per chip.
I would use one gate to make the tone (eg; 600 Hz), then another one to set the beep duration - eg: 2 Hz for a half second tone burst,. The other two gates can be used to buffer the first.
Having a quick search, you might get close to what you need here:-
https://www.qsl.net/dl4mea/roger.htm
73s
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