Various recruiters (UK) produce surveys of salaries. Clearly it is in their interest to inflate these numbers. YMMV etc.

https://viaresource.com/wp-content/uploads/2022/02/Information-and-cyber-security-salary-guide.pdf

https://www.barclaysimpson.com/resources/BSA%20Salary%20Guide%20v7.pdf

https://intaso.co.uk/salary-calculator-tool/

The Infosec income questionnaire. Fairly international

https://docs.google.com/forms/d/e/1FAIpQLSfwJPoFoUhrQMpDv3fwa8ItcZHwriIjLDBkAiFalXXNp88bFA/viewform

https://docs.google.com/spreadsheets/d/1TWvPQalmwl1sIS3n2eOU4KST4oJwcxtSfT8lMo9IgVM/edit#gid=691164905

Some useful advice

https://fearlesssalarynegotiation.com/articles/

https://fearlesssalarynegotiation.com/salary-expectations-interview-question/