I got one off ebay for 40 bucks and the orange snap ring for another 15 which you have to replace.
The snap ring is a pain to remove and install, the ford tool is useless. I used a pick set to remove the metal clip spring thing and pull the orange plastic out. Essentially destroying it. Best method I have found is to use a socket that will fit in the space and tap it on with hammer. Then use a screwdriver to lightly slide into place. If you run manual hubs you can skip replacing the seals, (which you need tools for too) as air sealing is less critical. As long as you see no tears in the rubber you are good to go.
99 x-cab 4x4 4.0l auto
mods, cranked t-bars, silencer delete, k&n drop in, Rebuilt trans ,Trans Go stage 3 shift kit, 3200stall Fuddle Racing Torque Converter,
VANIR 63mm TB, Roush split rear exit exhuast, E-Fan, JBA Headers
Auto up/down both windows, OHC, EATC (soon to be modded)
03 Crown Victoria Police Interceptor