here's a link to the other thread --
http://forums.pelicanparts.com/porsche-911-technical-forum/1043068-where-buy-cylinder-head-temp-sensors.html
note that it doesn't look like the CHT addressed in that post was a BMW part after all -- looks like (at least for now), we're stuck with the $260 Porsche part as the only real option, with the Bosch-numbered part generally unavailable