Hey Mike- it's a fairly common mod to cut about 3 inches off the end of the stock silencer -- I'm told it improves performance....
Anyway, I'd disassemble the silencer to see if the SA was reinstalled. If the job was done right, the SA will still be useable and operable in the shorter silencer (it's actually attached to the endcap). As far as sound output, I'd think you'll be OK with the shorter silencer. I saw somewhere that Lafferty runs a shortened stock silencer, maybe the guys at Lansing Cycle will know if the sound level is within limits.
But, if you really want to buy a new silencer, I see all kinds of FMF TurbineCore II silencers at the enduro's, so they must be OK....
Enjoy the new bike; I guess I'll have to buy a new one to keep up with you now!:cool: