Excellent, looks like the K5SS. I have a K5A myself - the newer SS's are somewhat easier to get parts for still. As others have mentioned it's not a bad idea to tear into it and replace the grease (and gasket). It's an afternoon job and will give that mixer a new lease on life for $20.

You'll also be able to get under the trim ring and seams where the castings meet and give it a very satisfying deep clean!