I saw this: Car Part Wholesale - Auto Parts and Accessories Catalog - Denso Rear Oxygen Sensor - Direct OE replacement is this the real OEM?
I usually get parts from my local Toyota dealer or one of the Toyota dealers that sell parts on line. Good luck!
If the OP wants to try this vendor, I suggest that he find the wiring harness connector for the oxygen sensor, disconnect it, and compare its appearance to the photo.
Doesn't matter bud.. O2 is an o2.. go save money and go to autozone or some local store.. get the O2 wrench to remove it and install it.. takes maybe 5 minuets