We finally found an Italian source of the OEM Piaggio MP3 Tilt Lock Pressure Sensor. It is made in the same Italian factory and identical in every way to the one that came in your new MP3, but is a whole lot cheaper at $79
I still have some of this part that we bought from Piaggio, and they are what I consider expensive at $139 (which I'm told is a deal), until we sell through. They are in the finest Piaggio plastic bags, with a handsome Piaggio parts label, so you can still pay an additional $60 for the same part in a designer plastic bag and label, that might be suitable for framing if you don't tear it open with your teeth.
https://scooterpartsco.com/main-category-c-801_4181_4187/tilt-lock-pressure-sensor-for-piaggio-mp3-640295-p-37836.html
Same part, a little overpriced, but in a handsome Piaggio plastic bag.
https://scooterpartsco.com/030-piaggio-c-801_836/tilt-lock-pressure-sensor-for-piaggio-mp3-640295-p-22309.html