yeah ya right when ya think about it $350 for new 140cc motor inc. postage, IRK + Lightened oil slinger + CDI about $120 dollars postage(if you look carefully enough there are packs with the IRK,slinger and CDI), + dress up kit. your really looking at about $450-$500, then you'll need to know how to fit it all properly.
only done side is that its the 138cc not the 140cc so it could really be a 127cc which would not be worth the $500.