I believe you are looking for these:
21 IH-377959-R91 Oil Seal, Reduction Drive Shaft
And unfortunately (NLA):
18 ~NLA Bearing, Reduction Drive Shaft Front
But, look at diagram to verify it is what you were wanting:http://www.cubcadet.com/webapp/wcs/stor ... 0118500011
I am sure one can be matched up at a good parts supplier.
OH, good looking O, like the fenders!