From the pics, that mower looks salvagable. Strip the mower down to the deck, take it in and have it media blasted inside and out. Get $30 in self-etching primer and grabber green paint. Also pick up some metal-prep for the pitted areas of rust (after media blasting) and repaint. Get some new parts to replace worn out or beat up ones....could look like mine. Mine runs very well couldn't let it go to the scrap yard.