If you ARE looking for an SME 20, I just noticed an SME 20/2 for sale today for $7,950 with an SME IV.vi arm (which you could easily sell for over $1000 thus getting this in your price range). I am an SME 30 owner but have no idea what an SME 20 sounds like, particularly compared to the highly regarded Teres - I just thought I'd bring your attention to this ad. I actually think I have sold some amps to this guy.
Good luck in your hunt.
Good luck in your hunt.