Xerox Phaser 8550

Question

out of warranty, but prints cleaning pages at its own wim !  called Xerox, their techi suggested a download which did not work.  local repairman says it is printhead going out, which costs more than new machine...i don't understand Xerox's pollicies on this.  nevertheless, does anyone have parts from dismantled machine ?  or any suggestions ?

thanks
maxine