360 magnum value?

thinking of selling my 360 magnum crate engine but dont know what to ask.what should i ask?
360 magnum,hughes 544/228 roller cam,rpm air gap,holley 750 ultra hp carb,mp dizzy.i bought this new several years ago.always run synthetic oil.uses absolutly no oil.i would quess it to be @375 h.p. as it was the 300 hp motor before i added the cam,intake,carb.any ideas on what to ask