cable tie them together then wrap in bubble wrap, then wrap and tape cardboard around them,then put them into black bags and the use the thick brown sellotape and bind them altogether a box will be hard to come by and normally rip the cardboard and become damages unless is a specific box for the part with reinforced cardboard ect,
they are not very good at sending the correct items , had similar probs getting the correct secondry decat pipe off them , say the one I have spare here from them would fit to your your car , sent me the long one instead of the short one