I never understood why people think the B&M or Schnell's are notchy? The B&M really is not (and I suspect the Schnell isn't either). Just crisp and much shorter throws. Now, if you try it on a car w/out the engine running it does feel notchy....
Anyhow, to sell it I'm afraid your best bet is to match what these sell for new now a days. They aren't as expensive as when I (and I presume you) bought 'em). Most online distributors now
sell them for $199 (look under products). I can understand why you wouldn't want to lose a lot of $ on a new part you bought so I say you should just install. You'll love the feel w/ the SSK.
Good luck