Well, SB 9, in decent condition is say around 1000 USD or 1300 CAD.
More if its in decent condition and comes with lots of stuff.
If it is rusted, in poor shape etc. it can be just few hundred $.
I don't even know which SB 9 headstock you have - but who exactly would want just a headstock? For parts? Repairing a lathe? Building your own lathe? I say if it is non flat belt model in great shape maybe someone buys it from between $100 to maybe $300. You may have to wait years before you find a buyer - or days if someone on her needs one
Dabbler would be better at this than me, I think.