You can get wideband O2 sensors, but they wont be very useful in your application. The W/B sensors will run around 0-5v while the Toyota oscillates between 0-1v i believe. You can get the W/B for as cheap as $28 or over $200 but the factory ECU wont read the signal since its looking for an oscillation betwen 0-1v. You can get a WideBand controller like the Innovative Motorsports LM-1 which alot of people use around here, but only for performance purposes. Unless youre changing your fuel curves or going forced induction, the stock O2 sensors should work fine