you can just go to any auto part store and get them (bosch) now if you happen to have long tube headers i found that if you tell them it is for a cobra the wires are longer i beleive.so you will not have to get extentions. well thats the way it wa son my 93.
I have the Bosch ones from advanced autoparts and bosch makes different lengths that will work for our cars I have the long ones and will not have to get O2 extensions when I get long tubes.
i work for advance auto i sell the bosch sensors daily ive never had a single complaint on them and i also run them in my s10 with absoultly no problems and i got great reading out of them a 4 wire sensor should run you anywhere from 50 to 80 $.
Just to throw a little more discussion in there on this topic .....
I've heard somewhere that you don't necessarily have to extend the o2 sensor wiring for LT's, and that there is a way around it (I believe it was by undoing some mounting points on the wiring). Is this true?
I just bought #13127 a couple weeks ago and I have longtubes. I have heard though that with longtubes and the position of the sensor being farther back that sometimes O2 sensors can give false readings and that Motorcraft sensors deal with this better than Bosch.