I know some guys have the TPMS on there 987 and absolutely hate them. Plus they are another expense when replacing tires. Heard countless stories about them getting damaged and triggering the lights when the tire is just fine. You might find someone with a 987 that would gladly give them to you if they can.
On my 05 pre TPMS, I have the valve measurement kind. Its Green when the pressure is good and turns Red when it starts to drop below the limit. Easy to tell with a quick walk around the car before driving off. Not sure if this will work for your purpose but its been working fine so far.
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