Help:2007 toyota Sienna Tire pressure sensor

One tire is leaking air very slowly, took it to dealer this morning and was told the tire pressure sensor is broken and is not coverred by the extended warranty. The deal ask for $250 for the parts and labor to change the sensor in the tire.

I know it is a redundant system, so I think I have 2 options:

1. Try to disable the Tire Pressure Monitor System. (anyone knows how to do it). As I don't want to waste similar money when I need to change new sets of tires in the future.

2. Buy a OEM sensor on line and ask the dealer to install it (basically they code the frequency into the computer), they ask $98 for coding (a rip-off)

Any one has similar experiences? Better solutions? Thanks