Eight years is old. You could replace it with the same brand or another of the same type. It’s a good proven sensor. They make them for just rain, freeze, or rain/freeze. I’d get the rain/freeze version. I like the wired because it’s direct connected and no batteries.
Just be ready for the alerts in the cold season! It freezes at night and warms during the day, here in North Texas anyway. Since the alert is for rain, it’ll be that way for freezing too until an option is available to add a separate freeze sensor.