Does something like this exist?
The Apple Watch 4 or 5, Garmin Vivosmart 4 fitness monitor, and the Samsung Gear Watch all have heart monitor functions which can notify you of high stress levels.
The Garman device is noticeably less expensive, but then it doesn’t have all the other smart watch features, not even GPS tracking. It’s a fitness band.
It’s quite likely that at least one of these will be on sale for Black Friday if you want to wait until then.
I’m not sure exactly how you would tie the alerts into anything else, though, you would have to investigate that based on each model.
The Apple Watch has been pretty thoroughly tested by some health providers and seems to be quite accurate. Several insurance companies are now including it in their heart healthy programs for that reason.