Never done it, but looking at the manual it looks easy enough to try it. However you are going to have to find the seals. You could look at your local bearing/seal shop, just don't scare them enough they can't read the numbers or take measurments. Anyway, according to the manual you can use a seal pick to remove the dust seal and seal. I would not remove/replace the bearing on top of the main seal though.
(6) Remove pitman shaft from the side cover.
(7) Remove dust seal from the housing with a seal
CAUTION: Use care not to score the housing bore
when prying out seals and washer.
(8) Remove retaining ring with snap ring pliers.
(9) Remove washer from the housing.
(10) Remove oil seal from the housing with a seal