the seal is still available from agco. When I was having an issue rebuilding my hydraulic pump I called my local agco dealer and they told me exactly what i needed to know. try calling youre dealer for help about the gear. I think you're talking about the steering shaft oil seal. if you are this is the part# 70222208.
to look for other part numbers check out the agco parts website. you have to view it as a guest and search for wd45 to get to the correct page you're looking for.