First of all, go here http://agcopartsbooks.com/PartsBooksN/Viewer/book.aspx?book=agco/651157
and find your part number. From there, you might get lucky with some online searching. Parts for these are getting fewer and further between. You may also consider doing some of what I like to call "redneck engineering" to find a work around for the issue, if parts are not available.
I've been lucky with mine a few times finding new old stock parts on ebay and other places.