replacing windows clasps

[Down__Under]

HI,
I've got these winders that are ok, but not lockable. They are paired up with these swanneck handles that are also not lockable. If i replace the handles are there any ways to fit something that is more potentially secure / lockable. I would prefer to avoid anything with keys more like a secure latch or handle. Even a restricted opener that allows only small opening as the house is climate controlled centrally.

The swannecks hadnles are pre-drilled two pin secured

Thanks in advance

 

[foxhole]

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