you could always get an insurance quote from KTAC to get a wholesale market value. currently they list my M8540 hd 12 speed open station (0'8 model) @ 28+k
so yours could be somewhere mid 25k or so. just a guess. you model will be sought after given that it's pre Tier 4. having a maintenance log really helps in resale
don't settle for less given all the high priced newer models today w/ Tier 4 technology