I honestly haven't thought about it too much. I think you can get a cheapie bluetooth watch to send you an alert if its nearby.

You can probably enable Google's find my if you want, but then what's the point of having a secure phone if Google always knows where you are?

Not too be to defeatist about things--there may be a solution out there for you--but a lot of the conveniences of modern life require trade-offs that we are encouraged to not think about.