For my oregon 450 (pressure, rather than capacitive), I just bought a few cheap ones for a random phone and cut them to size with scissors. Doesn’t affect operation, and has prevented light scratching, although nothing protects against sliding over granite.
I have a 650 too with capacitive screen (pinch, etc) but haven’t bothered as it doesn’t stay running long enough to get damaged, preferring to lock up randomly instead. So it mostly stays in my bag as a spare.
